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61.
The catechol-O-methyltransferase (COMT) enzyme is a major determinant of prefrontal dopamine levels. The Val158Met polymorphism affects COMT enzymatic activity and has been associated with variation in executive function and affective processing. This study investigated the effect of COMT genotype on the flexible modulation of the balance between processing self-generated and processing stimulus-oriented information, in the presence or absence of affective distractors. Analyses included 124 healthy adult participants, who were also assessed on standard working memory (WM) tasks. Relative to Val carriers, Met homozygotes made fewer errors when selecting and manipulating self-generated thoughts. This effect was partly accounted for by an association between COMT genotype and visuospatial WM performance. We also observed a complex interaction between the influence of affective distractors, COMT genotype and sex on task accuracy: male, but not female, participants showed a sensitivity to the affective distractors that was dependent on COMT genotype. This was not accounted for by WM performance. This study provides novel evidence of the role of dopaminergic genetic variation on the ability to select and manipulate self-generated thoughts. The results also suggest sexually dimorphic effects of COMT genotype on the influence of affective distractors on executive function.  相似文献   
62.
The present study aimed at measuring seropositivities for infection by Ascaris suum and Toxocara canis using the excretory/secretory (E/S) antigens from Ascaris suum (AES) and Toxocara canis (TES) within an indigenous population. In addition, quantification of cytokine expressions in peripheral blood cells was determined. A total of 50 Warao indigenous were included; of which 43 were adults and seven children. In adults, 44.1% were seropositive for both parasites; whereas children had only seropositivity to one or the other helminth. For ascariosis, the percentage of AES seropositivity in adults and children was high; 23.3% and 57.1%, respectively. While that for toxocariosis, the percentage of TES seropositivity in adults and children was low; 9.3% and 14.3%, respectively. The percentage of seronegativity was comparable for AES and TES antigens in adults (27.9%) and children (28.6%). When positive sera were analyzed by Western blotting technique using AES antigens; three bands of 97.2, 193.6 and 200.2 kDas were mostly recognized. When the TES antigens were used, nine major bands were mostly identified; 47.4, 52.2, 84.9, 98.2, 119.1, 131.3, 175.6, 184.4 and 193.6 kDas. Stool examinations showed that Blastocystis hominis, Hymenolepis nana and Entamoeba coli were the most commonly observed intestinal parasites. Quantification of cytokines IFN-γ, IL-2, IL-6, TGF-β, TNF-α, IL-10 and IL-4 expressions showed that there was only a significant increased expression of IL-4 in indigenous with TES seropositivity (p < 0.002). Ascaris and Toxocara seropositivity was prevalent among Warao indigenous.  相似文献   
63.
目的探讨前路椎体次全切除术和后路椎管扩大椎板成形术对脊髓型颈椎病(CSM)合并椎管狭窄症患者术后疗效及颈椎矢状位参数的影响。方法回顾性分析2010年3月—2015年8月收治的147例CSM合并椎管狭窄症患者的临床资料,其中80例行前路椎体次全切除术治疗(A组),67例行后路椎管扩大椎板成形术治疗(B组)。比较2种手术方法治疗前后日本骨科学会(JOA)评分、Cobb角及矢状位垂直距离(SVA)。将2组患者根据T_1倾斜角分别分为高T_1倾斜角(≥25°)亚组和低T_1倾斜角( 25°)亚组,对不同亚组之间的疗效及手术安全性进行比较。结果 2组术后JOA评分和Cobb角均高于术前,差异有统计学意义(P 0.05)。A组术后SVA低于术前,差异有统计学意义(P 0.05),B组术后SVA与术前相比差异无统计学意义(P 0.05)。A组术后JOA评分和Cobb角均高于B组,SVA低于B组,差异均有统计学意义(P 0.05)。A组中,高T_1倾斜角亚组和低T_1倾斜角亚组JOA评分改善效果和后凸畸形发生率比较差异无统计学意义(P 0.05);B组中,低T_1倾斜角亚组JOA评分改善效果和后凸畸形发生率优于高T_1倾斜角亚组,差异均有统计学意义(P 0.05)。结论相较于后路椎管扩大椎板成形术,前路椎体次全切除术治疗CSM合并椎管狭窄症临床疗效更佳,且有助于改善颈椎矢状位平衡;在高T_1倾斜角水平下,应尽可能选择前路椎体次全切除术。  相似文献   
64.
PurposeTo compare morphological imaging features and CT texture histogram parameters between grade 3 pancreatic neuroendocrine tumors (G3-NET) and neuroendocrine carcinomas (NEC).Materials and methodsPatients with pathologically proven G3-NET and NEC, according to the 2017 World Health Organization classification who had CT and MRI examinations between 2006-2017 were retrospectively included. CT and MRI examinations were reviewed by two radiologists in consensus and analyzed with respect to tumor size, enhancement patterns, hemorrhagic content, liver metastases and lymphadenopathies. Texture histogram analysis of tumors was performed on arterial and portal phase CT images. images. Morphological imaging features and CT texture histogram parameters of G3-NETs and NECs were compared.ResultsThirty-seven patients (21 men, 16 women; mean age, 56 ± 13 [SD] years [range: 28-82 years]) with 37 tumors (mean diameter, 60 ± 46 [SD] mm) were included (CT available for all, MRI for 16/37, 43%). Twenty-three patients (23/37; 62%) had NEC and 14 patients (14/37; 38%) had G3-NET. NECs were larger than G3-NETs (mean, 70 ± 51 [SD] mm [range: 18 - 196 mm] vs. 42 ± 24 [SD] mm [range: 8 - 94 mm], respectively; P = 0.039), with more tumor necrosis (75% vs. 33%, respectively; P = 0.030) and lower attenuation on precontrast (30 ± 4 [SD] HU [range: 25-39 HU] vs. 37 ± 6 [SD] [range: 25-45 HU], respectively; P = 0.002) and on portal venous phase CT images (75 ± 18 [SD] HU [range: 43 - 108 HU] vs. 92 ± 19 [SD] HU [range: 46 - 117 HU], respectively; P = 0.014). Hemorrhagic content on MRI was only observed in NEC (P = 0.007). The mean ADC value was lower in NEC ([1.1 ± 0.1 (SD)] × 10−3 mm2/s [range: (0.91 - 1.3) × 10−3 mm2/s] vs. [1.4 ± 0.2 (SD)] × 10−3 mm2/s [range: (1.1 - 1.6) × 10−3 mm2/s]; P = 0.005). CT histogram analysis showed that NEC were more heterogeneous on portal venous phase images (Entropy-0: 4.7 ± 0.2 [SD] [range: 4.2-5.1] vs. 4.5 ± 0.4 [SD] [range: 3.7-4.9]; P = 0.023).ConclusionPancreatic NECs are larger, more frequently hypoattenuating and more heterogeneous with hemorrhagic content than G3-NET on CT and MRI.  相似文献   
65.
PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%.  相似文献   
66.

Objective

The “Centre Hospitalier Francois Dunan” is located on an isolated island and ensures patients care in hemodialysis thanks to telemedicine support. Many research studies have demonstrated the importance of hemodialysis fluids composition to reduce morbidity in patients on chronic hemodialysis. The aim of this study was to identify the risks inherent in the production of dialysis fluids in a particular context, in order to set up an improvement action plan to improve risk control on the production of dialysis fluids.

Methods

The risk analysis was conducted with the FMECA methodology (Failure Mode, Effects and Criticality Analysis) by a multi professional work group. Three types of risk have been reviewed: technical risks that may impact the production of hemodialysis fluids, health risks linked with chemical composition and health risks due to microbiological contamination of hemodialysis fluids.

Results

The work group, in close cooperation with the expert staff of the dialysis center providing telemedicine assistance, has developed an action plan in order to improve the control of the main risks brought to light by the risk analysis.

Conclusion

The exhaustive analysis of the risks and their prioritisation have permitted to establish a relevant action plan in this improving quality of dialysis fluids approach. The risk control of dialysis fluids is necessary for the security of dialysis sessions for patients, even more when these sessions are realized by telemedicine in Saint-Pierre-et-Miquelon.  相似文献   
67.
目的提出坐骨重叠征(ischium overlap sign,IOS)的概念,并分析其与发育性髋关节脱位(developmental dysplasia of the hip,DDH)手术后再脱位的关系。方法回顾性分析2013年9月至2017年5月山东大学附属省立医院治疗的88例(105髋)DDH患儿病例资料,其中男童16例、女童72例;平均年龄12(5~24)个月,平均随访时间34(15~59)个月;双侧17例,左侧63髋,右侧42髋;1髋为髋臼发育不良,11髋半脱位,93髋全脱位。术中行髋关节造影检查,按照Bowen标准选择闭合或切开复位石膏固定术。IOS是指在人类位髋关节造影平片上股骨头软骨内缘与坐骨外缘的重叠关系,二者重叠为Ⅰ度,相接为Ⅱ度,分离为Ⅲ度。将93髋全脱位按照IOS分度进行分组,比较组间再脱位发生率。结果 1髋髋臼发育不良和11髋半脱位者IOS均为Ⅰ度。93髋全脱位中IOSⅠ度14髋,Ⅱ度39髋,此两组均行闭合复位石膏固定,无再脱位病例;Ⅲ度40髋中,闭合复位石膏固定17髋,6髋再脱位;切开复位石膏固定23髋,1髋再脱位。本研究发现Ⅲ度组的再脱位发生率(7/40,17.5%)高于其他两组(P=0.006)。IOS为Ⅲ度的40髋中,闭合复位的再脱位发生率(6/17,35.3%)高于切开复位(1/23,4.4%),差异有统计学意义(X^2=4.518,P=0.034)。结论 IOS与DDH术后再脱位有一定的关系,IOS为Ⅲ度的髋关节如行闭合复位,再脱位的风险较高。  相似文献   
68.
69.
目的比较3%高渗盐水和20%甘露醇治疗重症动脉瘤性蛛网膜下腔出血所致颅内压增高的疗效.方法25例动脉瘤性蛛网膜下腔出血患者出现颅内压增高事件时, 随机交替接受等渗透剂量的160 mL 3%高渗盐水与150 mL 20%甘露醇进行降低颅内压治疗, 连续监测患者颅内压、平均动脉压、脑灌注压及中心静脉压.记录有效降低颅内压持续时间、颅内压最大降幅及其时间, 用药前及用药后1 h、3 h血钠水平及血浆渗透压.结果3%高渗盐水和20%甘露醇均可降低颅内压(均 P < 0.01), 两者的降低颅内压作用持续时间及颅内压降幅差异均无统计学意义(均 P >0.05).患者脑灌注压较用药前均上升(均 P < 0.01), 平均动脉压先上升后下降, 但差异无统计学意义( P >0.05).患者中心静脉压稍有波动, 但差异均无统计学意义(均 P >0.05).20%甘露醇治疗后患者血钠下降, 3%高渗盐水治疗后患者血钠值上升, 变化均有统计学意义(均 P < 0.05).20%甘露醇及3%高渗盐水治疗后患者血浆渗透压均先上升后下降, 变化均有统计学意义(均 P < 0.01). 结论3%高渗盐水可作为治疗动脉瘤性蛛网膜下腔出血所致颅内压增高患者的一线治疗药物.  相似文献   
70.
The acquisition of chemoresistance remains a major cause of cancer mortality due to the limited accessibility of targeted or immune therapies. However, given that severe alterations of molecular features during epithelial‐to‐mesenchymal transition (EMT) lead to acquired chemoresistance, emerging studies have focused on identifying targetable drivers associated with acquired chemoresistance. Particularly, AXL, a key receptor tyrosine kinase that confers resistance against targets and chemotherapeutics, is highly expressed in mesenchymal cancer cells. However, the underlying mechanism of AXL induction in mesenchymal cancer cells is poorly understood. Our study revealed that the YAP signature, which was highly enriched in mesenchymal‐type lung cancer, was closely correlated to AXL expression in 181 lung cancer cell lines. Moreover, using isogenic lung cancer cell pairs, we also found that doxorubicin treatment induced YAP nuclear translocation in mesenchymal‐type lung cancer cells to induce AXL expression. Additionally, the concurrent activation of TGFβ signaling coordinated YAP‐dependent AXL expression through SMAD4. These data suggest that crosstalk between YAP and the TGFβ/SMAD axis upon treatment with chemotherapeutics might be a promising target to improve chemosensitivity in mesenchymal‐type lung cancer.

Abbreviations

AUC
area under the curve
AXL
AXL receptor tyrosine kinase
BCL2
B‐cell lymphoma 2
CTD2
cancer target discovery and development
CTGF
connective tissue growth factor
DEG
differentially expressed genes
DOXO
doxorubicin
EMT
epithelial–mesenchymal transition
Eto
etoposide
FDA
Food and Drug Administration
ITGB3
integrin beta‐3
MAPK
mitogen‐activated protein kinase
MMP2
matrix metalloproteinase‐2
MMP9
matrix metalloproteinase‐9
mRNA
messenger RNA
NF‐κB
nuclear factor kappa‐light‐chain‐enhancer of activated B cells
SBE
SMAD binding element
SERPINE1
serpin family E member 1
siRNA
small interfering RNA
ssGSEA
single‐sample gene set enrichment analysis
TCGA
The Cancer Genome Atlas
TGFβ
transforming growth factor beta
YAP
Yes‐associated protein
YAP8SA
mutants of inhibitory phosphorylation site at eight serine to Alanine of YAP
ZEB1
zinc finger E‐box binding homeobox 1
ZEB2
zinc finger E‐box‐binding homeobox 2
  相似文献   
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