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1.
目的 观察结肠癌HCT116细胞健脾消癌方的条件培养液对HUVEC细胞管腔形成的影响,从PI3K/Akt生物轴调控角度探讨其作用机制。方法 培养HCT116细胞,细胞设3组:对照组,健脾消癌方组(加入15%健脾消癌方含药血清)及人参皂苷Rg3组;制备HCT116细胞健脾消癌方条件培养液(分组及制备方法见实验方法),用条件培养液干预HUVEC(脐静脉内皮细胞,Human Umbilical Vein Endothelial Cells),Matrigel基质胶法检测HCT116细胞健脾消癌方条件培养液对HUVEC小管形成的影响。随后采用蛋白免疫印迹法(Western blot)检测各组HCT116细胞磷脂酰肌醇3-激酶(PI3K)、蛋白激酶B(Akt)、p-Akt、VEGF(血管内皮生长因子,Vascular endothelial growth factor)蛋白表达。最后在结肠癌HCT116荷瘤小鼠中验证健脾消癌方对肿瘤生长速度的影响,并经瘤组织VEGF蛋白表达、CD31免疫组化染色检测肿瘤内血管生成情况。结果 模型组HUVEC细胞管腔形成较空白血清组显著增加(P<0.05);健脾消癌方组及人参皂苷Rg3组较模型组HUVEC细胞管腔形成显著减少(P<0.01)。p-Akt和VEGF蛋白表达水平模型组高于空白血清组(P<0.05),健脾消癌方组及人参皂苷Rg3组显著低于模型组(P<0.01);PI3K、Akt蛋白表达量组间差异无统计学意义。与对照组比较,模型组荷瘤小鼠肿瘤体积显著性增大,瘤组织内VEGF表达、CD31阳性面积显著性增加,差异有统计学意义(P<0.05);与模型组比较,健脾消癌方组及人参皂苷Rg3组荷瘤小鼠肿瘤体积显著减小,瘤组织内VEGF表达、CD31阳性面积降低,差异有统计学意义(P<0.05)。结论 健脾消癌方可抑制肿瘤的血管生成和生长,其作用机制可能与PI3K/Akt生物轴调控VEGF表达有关。  相似文献   
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PurposeAccording to the social determinants of health framework, income inequality is a potential risk factor for adverse mental health. However, few studies have explored the mechanisms suspected to mediate this relationship. The current study addresses this gap through a mediation analysis to determine if social support and community engagement act as mediators linking neighbourhood income inequality to maternal anxiety and depressive symptoms within a cohort of new mothers living in the City of Calgary, Canada.MethodsData collected at three years postpartum from mothers belonging to the All Our Families (AOF) cohort were used in the current study. Maternal data were collected between 2012 and 2015 and linked to neighbourhood socioeconomic data from the 2006 Canadian Census. Income inequality was measured using Gini coefficients derived from 2006 after-tax census data. Generalized structural equation models were used to quantify the associations between income inequality and mental health symptoms, and to assess the potential direct and indirect mediating effects of maternal social support and community engagement.ResultsIncome inequality was not significantly associated with higher depressive symptoms (β = 0.32, 95%CI = −0.067, 0.70), anxiety symptoms (β = 0.11, 95%CI = −0.39, 0.60), or lower social support. Income inequality was not associated with community engagement. For the depression models, higher social support was significantly associated with lower depressive symptoms (β = −0.13, 95%CI = −0.15, −0.097), while community engagement was not significantly associated with depressive symptoms (β = 0.059, 95%CI = −0.15, 0.27). Similarly, for the anxiety models, lower anxiety symptoms were significantly associated with higher levels of social support (β = −0.17, 95%CI = −0.20, −0.13) but not with higher levels of community engagement (β = 0.14, 95%CI = −0.14, 0.41).ConclusionThe current study did not find clear evidence for social support or community engagement mediating the relationship between neighbourhood income inequality and maternal mental health. Future investigations should employ a broader longitudinal approach to capture changes in income inequality, potential mediators, and mental health symptomatology over time.  相似文献   
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背景 致密性骨炎(OCI)和其他疾病有时难以鉴别,探讨血清骨转换生化标志物可为OCI的鉴别诊断提供依据。 目的 探索女性OCI患者的血清骨转换生化标志物的水平变化及临床意义。 方法 回顾性选取2013年6月至2022年2月在北京积水潭医院门诊及住院诊断为OCI的61例女性患者作为观察组,年龄15~50岁,平均(33.8±6.6)岁,病程2周~15年。选择同期61例女性体检健康者作为对照组,年龄15~48岁,平均(35.6±7.6)岁。比较两组一般临床资料和血清骨转换生化标志物水平,并对血清骨转换生化标志物与病情相关指标进行相关性分析。 结果 观察组血清白蛋白(45.4±2.9)g/L低于对照组(46.5±2.8)g/L(t=2.190,P<0.05)。血清骨转换生化标志物比较结果显示,观察组血清1型胶原羧基末端肽β特殊序列(β-CTX)〔0.28(0.23,0.37)μg/L〕、N-端骨钙素(OC)〔13.1(11.2,16.2)μg/L〕、25-羟维生素D3〔25-(OH)VD3〕〔(14.1±5.1)μg/L〕低于对照组〔0.36(0.29,0.48)μg/L,15.6(13.7,17.3)μg/L,(17.5±6.6)μg/L〕(Z=-2.983、-3.255,t=3.081,P<0.05)。长病程亚组OC水平〔14.6(12.4,18.5)μg/L〕高于短病程亚组〔11.7(10.2,14.0)μg/L〕(Z=-2.407,P<0.05)。多孕亚组β-CTX〔0.25(0.22,0.32)μg/L〕、OC水平〔12.2(10.3,15.0)μg/L〕低于非多孕亚组〔0.33(0.26,0.44)μg/L、13.4(12.0,18.8)μg/L〕(Z=-2.486、-1.897,P<0.05)。相关性分析显示,观察组血清1型前胶原氨基端延长肽(tP1NP)与妊娠次数、生产次数均呈负相关(rs=-0.276、-0.298,P<0.05),OC与体质指数(BMI)、视觉模拟评分法(VAS)评分、妊娠次数均呈负相关(rs=-0.284、-0.374、-0.360,P<0.05),25-(OH)VD3水平与BMI呈正相关(rs=0.275,P<0.05)。 结论 女性OCI患者血清OC、β-CTX水平明显降低,可为鉴别其他疾病提供依据;血清OC水平可以反映OCI患者的严重程度,同时OC水平与患者妊娠次数相关;tP1NP与妊娠次数、生产次数相关。  相似文献   
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Breast core biopsies are a standard component of the triple approach that includes clinical examination, imaging and tissue sampling. Conventional cores, diagnostic vacuum assisted biopsy and vacuum assisted excisions are established methods for sampling and managing breast lesions. It is important to be aware of the potential pitfalls in the technical handling and interpretation of the limited core biopsy samples. Here, we present a clinically oriented, well illustrated overview of the common diagnostic pitfalls based on the author's diagnostic and second opinion practice, emphasize the value of clinicopathological correlation and provide histological tips and clues with useful immunohistochemistry to aid the reporting pathologists in their daily interpretation of breast core biopsies.  相似文献   
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BackgroundVitamin D is essential in the host defense against tuberculosis (TB). Suboptimal vitamin D status is common in the hemodialysis population. Hemodialysis patients have an increased risk compared to the general population latent tuberculosis infection (LTBI). However, the association between vitamin D deficiency and LTBI in this population remains unclear.Materials and methodsWe conducted a cross-sectional study between March and May 2017. Interferon-gamma release assay (IGRA) through QuantiFERON-TB Gold In-Tube was used to assess LTBI. Plasma 25-hydroxycholecalciferol (25-OHD) levels were measured by Elecsys Vitamin D Total assay. Suboptimal vitamin D levels included vitamin D insufficiency 20–29 ng/mg and vitamin D deficiency <20 ng/mL. Predictors for LTBI were analyzed.ResultsA total of 287 participants were enrolled. The suboptimal vitamin D level was 31.4% (90/287), which including the vitamin D deficiency was 13.9% (40/287). A total of 49.1% (141/287) people received nutritional vitamin D supplementation. The prevalence of IGRA positivity in this study was 25.1% (72/287). There was no significant difference in vitamin D concentrations or the proportion of vitamin D supplementation among the IGRA-positive and IGRA-negative groups (p = 0.789 and 0.496, respectively). In multivariate analysis, age >65 years old (odds ratio (OR), 1.89; 95% CI, 1.08–3.31; p = 0.026) and TB history (OR, 3.51; 95% CI, 1.38–8.91; p = 0.008) were independent predictors of IGRA positivity.ConclusionThis is the first study to report that vitamin D deficiency was not associated with IGRA positivity in a hemodialysis population. Aging and TB history were both independent predictors for LTBI.  相似文献   
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《Vaccine》2022,40(32):4296-4300
Advanced computational methodologies suggested SARS-CoV-2, nonstructural proteins ORF1AB, ORF3a, as the source of immunodominant peptides for T cell presentation. T cell immunity is long-lasting and compatible with COVID-19 pathology. Based on the supporting clinical data, nonstructural SARS-CoV-2 protein vaccines could provide global immunity against COVID-19.  相似文献   
10.
目的 运用核磁共振弥散张量成像技术(DTI),从皮质脊髓束损伤程度评价的角度,探讨肾虚髓亏证与急性缺血性脑卒中运动功能缺损程度相关性,丰富中风病病机及证候诊断,拓宽缺血性脑卒中的中医药防治思路,为急性缺血性脑卒中肾虚髓亏证患者运动功能损伤程度提供临床依据,强调肾虚髓亏证在急性缺血性脑卒中运动功能损伤中的重要意义。方法 纳入符合诊断标准的90例病例,根据证候分别归入肾虚髓亏组和非肾虚髓亏组,每组各45例。每组患者均给予常规西药治疗。对两组患者入院后行弥散张量成像检测,同时分别于治疗前及治疗后14天,记录两组患者NIHSS评分、改良Barthel指数量表及简化Fugl-Meyer运动功能评分量表评分,比较两组病例发病时的轻重程度及治疗前后两组病例组间的恢复差异。结果 研究显示,治疗前肾虚髓亏组在NIHSS评分方面高于非肾虚髓亏组(P<0.05);治疗前肾虚髓亏组在改良Barthel指数量表及简化Fugl-Meyer运动功能评分方面低于非肾虚髓亏组(P<0.05)。治疗前后NIHSS评分、改良Barthel指数评分及简化Fugl-Meyer运动功能评分改善情况,非肾虚髓亏组要优于肾虚髓亏组(P<0.05)。治疗前两组患者在健侧内囊后肢及大脑脚外侧处FA值及ADC值无明显差异;肾虚髓亏组在患侧内囊后肢及大脑脚外侧处FA值及ADC值均低于非肾虚髓亏组(P<0.05)。相关性分析得出,两组患者患侧内囊后肢FA值与患者治疗前NIHSS评分呈负相关;两组患者患侧内囊后肢FA值与患者改良Barthel指数评分及简化Fugl-Meyer运动功能评分呈正相关;肾虚髓亏组患者患侧内囊后肢FA值与肾虚髓亏证中医证候评分呈负相关。结论 肾虚髓亏是急性缺血性脑卒中运动功能障碍的重要病机。研究结果显示,两组皮质脊髓束损伤程度与神经功能及运动功能损伤存在相关性,且肾虚髓亏组在皮质脊髓束的损伤程度方面与其中医证候评分呈负相关。  相似文献   
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