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排序方式: 共有4116条查询结果,搜索用时 15 毫秒
1.
Cécile Vicier Lillian Werner Jonathan Chipman Lauren C. Harshman Dattatraya H. Patil Raina N. Fichorova Jennifer R. Rider Martin G. Sanda Lorelei A. Mucci Christopher J. Sweeney 《Clinical genitourinary cancer》2019,17(1):32-37
Background
Inflammation and infections have been associated with prostate cancer progression. We assessed whether elevated serum cytokines or T. vaginalis seropositivity at the time of diagnosis was associated with higher grade or lethal prostate cancer.Patients and Methods
Men with localized or metastatic prostate cancer were included in this study. Cytokine serum levels including interleukin (IL)-1α, IL-1β, IL-2, IL-6, IL-8, monocyte chemotactic protein 1 (CCL-2), tumor necrosis factor α, and growth-regulated oncogene α (CXCL-1) using a multiplex enzyme-linked immunosorbent assay and T. vaginalis serology were measured in blood samples at diagnosis.Results
A total of 324 patients were identified at time of localized disease and 118 at time of metastatic disease. Of the 189 patients with localized disease and clinical follow-up data (median, 73 months), 28 developed lethal disease. There was no association between circulating cytokine levels above median concentrations nor T. vaginalis seropositivity and risk of intermediate- to high-risk or lethal prostate cancer.Conclusion
Higher levels of serum cytokine levels and T. vaginalis seropositivity at diagnosis are not associated with high-grade or lethal prostate cancer and do not aid risk stratification of localized prostate cancer. 相似文献2.
Mani N Pavuluri Megan Marlow O'Connor Erin M Harral Melissa Moss John A Sweeney 《Neuropsychopharmacology》2006,60(9):951-956
BACKGROUND: Previous research has demonstrated that academic and neuropsychological functions are compromised in pediatric bipolar disorder (PBD). Investigation of the degree to which neuropsychological deficits might contribute to those academic problems is needed to aid in the recognition and intervention for school achievement difficulties in PBD. METHODS: A sample of 55 children and adolescents with PBD with and without attention-deficit/hyperactivity disorder (ADHD) (PBD group, n = 28; PBD+ADHD group, n = 27) were tested with a computerized neurocognitive battery and standardized neuropsychological tests. Age range of subjects was 7-17 years, with the mean age of 11.97 (3.18) years. Parents completed a structured questionnaire on school and academic functioning. RESULTS: Logistic regression analyses indicated that executive function, attention, working memory, and verbal memory scores were poorer in those with a history of reading/writing difficulties. A separate logistic regression analysis found that attentional dysfunction predicted math difficulties. These relationships between neuropsychological function and academic difficulties were not different in those with PBD+ADHD than in those with PBD alone. CONCLUSIONS: In PBD neuropsychological deficits in the areas of attention, working memory, and organization/problem solving skills all contribute to academic difficulties. Early identification and intervention for these difficulties might help prevent lower academic achievement in PBD. 相似文献
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Mani N Pavuluri Megan Marlow O'Connor Erin Harral John A Sweeney 《Neuropsychopharmacology》2007,62(2):158-167
BACKGROUND: Facial emotions are central to human interaction. Identifying pathophysiology in affect processing circuitry that supports the ability to assess facial emotions might facilitate understanding of affect regulation in pediatric bipolar disorder. METHODS: Ten euthymic, unmedicated pediatric bipolar patients and 10 healthy control subjects matched for age, gender, race, socioeconomic status, and IQ were scanned with functional magnetic resonance imaging. Angry, happy, and neutral faces were presented in 30-sec blocks, with a 20-sec rest period between blocks. Subjects were asked to press a button when each face appeared, to ensure that attention was maintained on-task. RESULTS: In bipolar patients, in response to both angry and happy faces relative to neutral faces, we observed reduced activation of right rostral ventrolateral prefrontal cortex together with increased activity in right pregenual anterior cingulate, amygdala, and paralimbic cortex. Bipolar patients also showed reduced activation of visual areas in occipital cortex together with greater activation in higher-order visual perceptual areas, including superior temporal sulcus and fusiform gyrus with angry faces and posterior parietal cortex with happy faces. CONCLUSIONS: Findings document a disturbance in affective neurocircuitry in pediatric bipolar disorder. Reduced activation in ventrolateral prefrontal cortex might reflect diminished top-down control that leads to the observed exaggerated activation in amygdala and paralimbic areas. Changes in occipital areas might represent an effort to gate sensory input when affective responses to the faces could not be successfully modulated. Disturbances in affect processing circuitry could contribute to emotional dysregulation and social cognitive difficulties in bipolar youth. 相似文献
5.
Changes to the ocular biota with time in extended- and daily-wear disposable contact lens use. 总被引:3,自引:0,他引:3
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F Stapleton M D Willcox C M Fleming S Hickson D F Sweeney B A Holden 《Infection and immunity》1995,63(11):4501-4505
Gram-negative bacteria may play a role in the etiology of certain soft contact lens (SCL)-related diseases. Contact lens (CL) wear may modify the normal ocular biota, providing a more favorable environment for potential pathogens. This study reports temporal changes in ocular biota in daily-wear (DW) and extended-wear (EW) disposable SCL use in experienced and neophyte wearers. Lid margin and bulbar conjunctival biota were sampled prior to CL fitting in 26 previous DW SCL users, 18 previous EW SCL users, and 26 neophytes. Wearers were fitted with an etafilcon A CL in one eye and a polymacon CL in the fellow eye. Lenses were worn on a daily basis by the 26 previous DW SCL wearers and on an EW basis by the remaining 44 subjects. The ocular biota was further sampled after 1, 3, 6, 9, and 12 months of wear. The ocular biota consisted of coagulase-negative staphylococci, Corynebacterium spp., Micrococcus spp., and Propionibacterium spp. Potential pathogens were rarely isolated at baseline. No significant trend of increasing ocular colonization was shown for extended CL wear. Lid and conjunctival colonization increased with DW SCL use (P < 0.001), although this increase occurred for nonpathogenic species only. Fewer potential pathogens were isolated from DW SCL than from EW SCL users (P < 0.05). The lid margin consistently showed greater colonization than the conjunctiva and may be a source of potential pathogens during CL wear. Hydrogel CL wear appears to modify the ocular biota. An increased number of commensal organisms were present in DW SCL use. EW SCL use altered the spectrum of organisms isolated. These alterations may suppress the normal ocular defense mechanisms and may be relevant in the pathogenesis of CL-related disease. 相似文献
6.
Suppurative corneal ulceration in Bangladesh 总被引:8,自引:0,他引:8
AAS Dunlop MB BS ED Wright MRCPath † SA Howlader‡ I Nazrul‡ R Husain‡ K McClellan FRACO § FA Billson FRACO § 《Clinical & experimental ophthalmology》1994,22(2):105-110
Suppurative keratitis is an important preventable cause of blindness, particularly in the developing world. This study analyses 142 cases of suppurative keratitis referred to Chittagong Eye Infirmary, Bangladesh. Some 53.5% of cases were bacterial and 35.9% were fungal. The five most common pathogens were: Pseudomonas sp. 24%, Streptococcus pneumoniae 17%, Aspergillus sp. 13%, Fusarium sp. 7% and Curvularia sp. 6%. Gram stain and culture results were consistent in 62.6% of cases. Previous antibiotic treatment was a significant factor for failure of culture isolation and less so for Gram stain failure. On Gram stain, 55.9% of pseudomonal cases were missed, but only 2% of fungal cases were missed. Over all, Gram stain had a sensitivity of 62% and positive predictive value of 84% for bacterial cases, and 98% and 94% for fungal cases, respectively. Fungal ulcers were typically filamentous, but an antecedent history of trauma was not common. The most frequent injury was due to rice grains, but the inoculum appeared to be introduced during eye washing with contaminated water. Pseudomonal ulcers occurred most frequently in the monsoon season, and Fusarium cases were seen only in the hot, dry season. 相似文献
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9.
Sun Weidong Hansell Stedman Chen Xiaoli Wei Yu Liu Meizhen Xu Chengbin H. Lee Sweeney 《中华医学杂志(英文版)》1998,(6):495
LigasechainreactionfordiagnosisoffamilialhypertrophiccardiomyopathySunWeidong孙维东,HanselStedman,ChenXiaoli,WeiYu,LiuMeizhen,Xu... 相似文献
10.
Nonheme iron in sickle erythrocyte membranes: association with phospholipids and potential role in lipid peroxidation 总被引:5,自引:0,他引:5
Previous studies documented the abnormal association of heme and heme proteins with the sickle RBC membrane. We have now examined RBC ghosts and inside-out membranes (IOM) for the presence of nonheme iron as detected by its formation of a colored complex with ferrozine. Sickle ghosts have 33.8 +/- 18.2 nmol nonheme iron/mg membrane protein, and sickle IOM have 4.3 +/- 3.0 nmol/mg. In contrast, normal RBC ghosts and IOM have no detectable nonheme iron. The combination of heme and nonheme iron in sickle IOM averages nine times the amount of membrane- associated iron in normal IOM. Kinetics of the ferrozine reaction show that some of this nonheme iron on IOM reacts slowly and is probably in the form of ferritin, but most (72% +/- 18%) reacts rapidly and is in the form of some other biologic chelate. The latter iron compartment is removed by deferoxamine and by treatment of IOM with phospholipase D, which suggests that it represents an abnormal association of iron with polar head groups of aminophospholipids. The biologic feasibility of such a chelate was demonstrated by using an admixture of iron with model liposomes. Even in the presence of tenfold excess adenosine diphosphate, iron partitions readily into phosphatidylserine liposomes; there is no detectable association with phosphatidylcholine liposomes. To examine the bioavailability of membrane iron, we admixed membranes and t-butylhydroperoxide and found that sickle membranes show a tenfold greater peroxidation response than do normal membranes. This is not due simply to a deficiency of vitamin E, and this is profoundly inhibited by deferoxamine. Thus, while thiol oxidation in sickle membranes previously was shown to correlate with heme iron, the present data suggest that lipid peroxidation is related to nonheme iron. In control studies, we did not find this pathologic association of nonferritin, nonheme iron with IOM prepared from sickle trait, high-reticulocyte, postsplenectomy, or iron-overloaded individuals. These data provide additional support for the concept that iron decompartmentalization is a characteristic of sickle RBCs. 相似文献