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Social media use by both teens and adults has become increasingly common. This frequency of interaction can be capitalized upon by researchers looking to design programs to limit youth substance use. This study serves as a first step in this area of research, examining how parent–child social media exchanges (specifically on Facebook) may be related to youth risk behavior. In a sample of 252 college students, results indicated that roughly 63% of youth reported being friends with their parents on Facebook while in high school. A minority (27%) reported they blocked their parents from seeing certain material on their Facebook page, and most youth reported their parents discussed information from their Facebook page with some regularity (65%). Logistic regression analyses indicated that, when accounting for demographics, parental solicitation, and parental control efforts, youth who were friends with their parents on Facebook and did not block any materials from them had a decreased likelihood of alcohol and/or marijuana use in high school relative to those who were not friends with their parents on Facebook or who blocked materials from their parents. These findings imply that efforts to encourage parent–child interactions via social media may help prevent substance use in high school.  相似文献   
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CD147 has been implicated in melanoma invasion and metastasis mainly through increasing metalloproteinase synthesis and regulating VEGF/VEGFR signalling. In this study, the prognostic value of CD147 expression was investigated in a cohort of 196 cutaneous melanomas including 136 consecutive primary malignant melanomas, 30 lymph nodes, 16 in‐transit and 14 visceral metastases. A series of 10 normal skin, 10 blue nevi and 10 dermal nevi was used as control. CD147 expression was assessed by immunohistochemistry, and the association of its expression with the clinicopathological characteristics of patients and survival was evaluated using univariate and multivariate statistical analyses. Univariate analysis showed that high CD147 expression was significantly associated with metastatic potential and with a reduced overall survival (P < 0.05 for both) in primary melanoma patients. CD147 expression level was correlated with histological factors which were associated with prognosis: Clark level, ulceration status and more particularly with Breslow index (r = 0.7, P < 10?8). Multivariate analysis retained CD147 expression level and ulceration status as predicting factors for metastasis and overall survival (P < 0.05 for both). CD147 emerges as an important factor in the aggressive behaviour of melanoma and deserves further evaluation as an independent prognostic biomarker.  相似文献   
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Gallbladder cancer (GBC) is the most common malignant tumor of the biliary tract system. Epithelial–mesenchymal transition (EMT) plays a vital role in the process of tumor metastasis. Mesenchymal‐like cells can serve as a source of cancer stem cells, which can confer the EMT phenotype. Placental growth factor (PLGF) belongs to the vascular endothelial growth factor family and plays a vital role in cancer. However, the underlying molecular mechanisms about the influence of PLGF on EMT in GBC remain unknown. Here we show that PLGF expression levels were higher in GBC tissues than in normal adjacent tissues and were associated with poor prognosis in GBC patients. Exogenous PLGF enhanced the migration, invasion, and tumorsphere formation of GBC cells. Conversely, knockdown of PLGF decreased the aggressive phenotype of GBC cells. Mechanistically, exogenous PLGF upregulated microRNA‐19a (miR‐19a) expression through the activation of c‐MYC. Moreover, Spearman's correlation analysis showed a positive pairwise correlation among PLGF, c‐MYC, and miR‐19a expression in GBC tissues. Taken together, these results suggest that PLGF promotes EMT and tumorsphere formation through inducing miR‐19a expression by upregulating c‐MYC. Thus, PLGF could be a promising molecular therapeutic target for GBC.  相似文献   
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提取20例胃癌及相应正常胃组织DNA为样品,PCR-SSCP方法快速筛查出4例胃癌组织中存在nm23-H_1基因突变。此结果支持nm23-H_1基因与肿瘤转移抑制密切相关。  相似文献   
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山东省沂蒙山区莱姆病自然疫源地调查   总被引:1,自引:0,他引:1  
目的 :调查山东省沂蒙山区莱姆病自然疫源地。方法 :1992~ 1999年设点 ,用间接免疫荧光抗体试验进行人群莱姆病感染调查 ;用直接免疫荧光抗体法进行蜱中肠带螺旋体率调查 ;取鼠的肾脏、膀胱分离病原。结果 :沂蒙山区人群莱姆病平均感染率为 7.50 % ,林区人群感染率明显高于非林区人群 ;该地区蜱类以长角血蜱为优势种 ,该蜱中肠携带莱姆病螺旋体率为 12 .0 % ,从86组长角血蜱培养物中获得 2株莱姆病螺旋体。结论 :从病原学上证实沂蒙山区为莱姆病自然疫源地  相似文献   
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本文报道375例白血病患者ABO血型分布。其中,O型143例(38.1%),A型126例(33.6%);B型85例(22.7%);AB型21例(5.6%)。发现一例急性粒细胞白血病患者的血型由A型变异为O型。并就血型与疾病的关系,血型变异的可能机理进行了引述讨论。  相似文献   
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