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1.
Rebekka Lencer Li Yao James L. Reilly Sarah K. Keedy Jennifer E. McDowell Matcheri S. Keshavan Godfrey D. Pearlson Carol A. Tamminga Elliot S. Gershon Brett A. Clementz Su Lui John A. Sweeney 《Human brain mapping》2019,40(1):163-174
Despite a growing number of reports about alterations in intrinsic/resting brain activity observed in patients with psychotic disorders, their relevance to well‐established cognitive control deficits in this patient group is not well understood. Totally 88 clinically stabilized patients with a psychotic disorder and 50 healthy controls participated in a resting‐state magnetic resonance imaging study (rs‐MRI) and performed an antisaccade task in the laboratory to assess voluntary inhibitory control ability. Deficits on this task are a well‐established biomarker across psychotic disorders as we found in the present patient sample. First, regional cerebral function was evaluated by measuring the amplitude of low frequency fluctuations (ALFF) in rs‐MRI BOLD signals. We found reduced ALFF in patients in regions known to be relevant to antisaccade task performance including bilateral frontal eye fields (FEF), supplementary eye fields (SEF) and thalamus. Second, areas with ALFF alterations were used as seed areas in whole‐brain functional connectivity (FC) analysis. Altered FC was observed in a fronto‐thalamo‐parietal network that was associated with inhibition error rate in patients but not in controls. In contrast, faster time to generate a correct antisaccade was associated with FC in FEF and SEF in controls but this effect was not seen in patients. These findings establish a behavioral relevance of resting‐state fMRI findings in psychotic disorders, and extend previous reports of alterations in fronto‐thalamo‐parietal network activation during antisaccade performance seen in task‐based fMRI studies. 相似文献
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Jaymie R. Meliker Caterina Vacchi-Suzzi James Harrington Keith Levine Li-Yung Lui Douglas C. Bauer Eric Orwoll Deborah M. Kado 《International journal of hygiene and environmental health》2019,222(2):230-234
Objectives
There is growing evidence that urine cadmium is a temporally stable biomarker indicative of long-term cadmium exposure; however questions remain with regard to generalizability to older persons, the impact of changes in smoking behavior, and the degree of temporal stability when repeat sample collection spans years instead of weeks or months.Methods
Using archived samples from cohorts of older men (Osteoporotic Fractures in Men (MrOS-US)) and women (Study of Osteoporotic Fractures (SOF)) (mean age?=?80?at study visit 2), we analyzed two morning urine samples each from 39 men and 18 women with a diverse self-reported smoking history. For MrOS, samples were collected approximately 6 years apart, and 4 years apart for SOF. Intra-class correlations were computed to assess temporal stability, and adjusted for age and body mass index.Results
The median creatinine-adjusted urinary cadmium levels (0.39?μg/g for men, 0.89?μg/g for women) were similar to levels expected for these age/sex groups in the US according to the National Health and Nutrition Examination Survey. The overall intra-class correlation was high (ICC?=?0.85; 95% CI: 0.76–0.91) and similar between cohorts (MrOS: ICC?=?0.74; 95% CI: 0.58–0.86; SOF: ICC?=?0.81; 95% CI: 0.59–0.93), but slightly lower among those who stopped smoking between visits of sample collection (ICC?=?0.64; 95% CI: 0.31–0.87) or among former smokers who quit prior to the first sample collection (ICC?=?0.68; 95% CI: 0.25–0.93).Conclusions
We report good-to-excellent reproducibility of urine cadmium using morning urine samples collected 4–6 years apart from older men and women, but slightly lower correlations among those with a history of smoking. Single measures of urine cadmium are a reliable biomarker in older men and women. 相似文献4.
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本研究对13例人的正常涎腺经三种固定双固定后的组织标本进行了11种角蛋白单克隆抗体的免疫组化染色.其中5例腮腺和3例颌下腺分别同时用常规Formalin固定,Bouin’s液固定,Carnoy‘s液固定.染色采用ABC法,结果发现:Carnoy固定者,K_8、K_18、K_19和K_8.12的染色效果最好.其导管染色比Bouin‘s和Formalin固定者染色强而明确,尤其K_8和K_8.12不仅在导管中呈现强阳性,而且腺泡也呈阳性;而K_(17)和K_(L1)没有看出明显的染色差别;K_(14)、K_(10)、K_(13)、K_(17)、K_(20)的染色几乎全为阴性,与常规中性缓冲Formalin固定者结果一致. 相似文献
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Squamous cell carcinoma antigen (SCCA) is traditionally engaged for detecting and following up malignancy from a squamous cell origin. We encountered an unusual increase of blood SCCA but no other cancer markers in a patient associated with an infective lumbar spondylitis due to Pseudomonas aeruginosa. An overshooting of Th1 expression, such as tumor necrosis factor alpha, bumped up by his uremia as a result of P. aeruginosa infection may hasten SCCA. Therefore, SCCA might additionally serve as a serological marker for infection besides squamous cell cancer, and its false-positive increase also highlights the appropriateness of tumor marker screening. 相似文献