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101.
Background: Patients with bladder cancer have a high risk of suicide. This study aimed to assess how bladder cancer increases suicide risk and to identify the demographic and clinical factors associated with suicidal death among patients with bladder cancer. Methods: Literature search of MEDLINE, PsycINFO, Embase, Web of Sciences and Cochrane Library databases was conducted up to April 2020 to identify eligible studies related to the incidence and risk factors of suicide after bladder cancer diagnosis. Summary multivariate-adjusted risk estimates and their associated 95% confidence intervals (CIs) were calculated using inverse variance method with random or fixed-effect modeling. Results: Five retrospective cohorts comprising 563,680 patients with bladder cancer were included. Higher risk of suicide by 1.90-fold was observed among patients with bladder cancer (hazard ratio, HR = 1.90, 95% CI: 1.29–2.81; P = 0.001; I2 = 81.2%), especially in those aged 70 years or older (HR = 1.36, 95% CI: 1.29–1.43; P < 0.001; I2 = 0%), unmarried (HR = 1.72, 95% CI: 1.61–1.83; P < 0.001; I2 = 0%), and those with regional bladder cancer (HR = 1.88, 95% CI: 1.10–3.21; P = 0.021; I2 = 96.3%), compared with those without bladder cancer. Furthermore, gender and race were not associated with increased suicide risk among patients with bladder cancer. Conclusions: Suicide risk is increased among patients with bladder cancer, particularly those aged 70 years or older, unmarried and those with regional bladder cancer. Hence, early psychological support must be provided during the follow-up period of these special populations with a high suicide risk.  相似文献   
102.
103.
目的 掌握北京市东城区牙科X射线机质量控制的基本状况,探讨辐射防护中存在的问题,为加强放射防护监管提供依据。方法 依据牙科X射线设备质量控制检测规范(WS 581—2017)对东城区18家医疗机构中的牙科X射线机进行检测和评价。结果 41台牙科X射线机总体合格率为92.68%,进口设备的合格率为100%,国产设备检测合格率为76.92%。6个性能检测指标中,“加载时间偏离”指标合格率为92.68%,“管电压指示的偏离”合格率为95.12%,其余性能指标合格率均为100%;机房防护水平全部合格。结论 北京市东城区牙科X射线机总体运行情况良好,但个别机构重视机房的放射防护,忽视口腔设备的质量控制检测。建议卫生行政部门、监管机构要加强对WS 581—2017标准的宣贯和普及力度,强化监督检查,加大处罚力度,提高各机构人员对牙科X射线机质量控制工作的重视程度,共同维护放射人员和公众的健康。  相似文献   
104.
用地高辛标记反意前阿黑皮素(pro-opiomelanocortin,POMC)cRNA探针原位杂交组化在光镜和电镜水平观察了POMC mRNA在大鼠垂体的分布,并比较了碱性磷酸酶(AKP)显色系统和辣根过氧化酶(HRP)显色系统在光镜水平上的敏感性.结果:POMC mRNA广泛地分布于垂体的中间叶和前叶.中间叶全部细胞均为POMC mRNA阳性.前叶中除前叶的腹侧缘和前叶与中间叶交界处阳性细胞较少外,都有较多的POMC mRNA阳性细胞分布.AKP显色系统比HRP显色系统敏感.在电镜水平,POMC mRNA主要分布于粗面内质网,少数分泌颗粒可能呈阳性反应,胞核未见阳性反应沉淀.文内还就阳性分泌颗粒在调节细胞合成功能方面可能起的作用进行了讨论.  相似文献   
105.
Akt/protein kinase B (PKB) plays an important role in cell survival. However, the role of Akt in the biology of gastric cancer has not been well studied. We sought to investigate the expression of Akt or phosphorylated Akt (pAkt) in human gastric carcinomas and to analyze the relationship between Akt or pAkt and the clinicopathologic parameters. The expressions of Akt and pAkt were evaluated immunohistochemically in 311 gastric carcinomas using the tissue array method. Akt expression was detected in 74% of the tumors and pAkt expression in 78%. pAkt was highly expressed in the early stage of pTNM (p=0.011). We also found an inverse association between pAkt and lymphatic invasion (p=0.01) or lymph node metastasis (p=0.008). pAkt expression was significantly correlated with a higher survival in patients with stage I carcinomas (p=0.0003). Interestingly, combined evaluation revealed that the group with pAkt-positive and lymph node-negative carcinomas showed a better prognosis than the other groups (p<0.0001). In addition, pAkt was shown to correlate positively with APC (p=0.002) and Smad4 (p<0.0001) expression. These findings suggest that pAkt expression may help to predict the clinical outcome of gastric cancer patients.  相似文献   
106.
107.
通过对小鼠补体受体Ⅱ型基因(CR2)进行定点突变,然后将野生型和突变型小鼠CR2/1(MCR2/1)及人CR2(hCR2)用电穿孔方法导入小鼠SP2/0进行表达,采用免疫组织化学等方法鉴定阳性细胞系。用EB病毒对转染阳性细胞进行感染,EBER-1杂交结果显示,仅转染hCR2和突变型MCR2(mtMCR2)的SP2/0细胞感染了EB病毒,前者感染EB病毒的阳性率较后者高很多。这为进一步研究EB病毒进入细胞的机制及建立EB病毒相关的鼻咽癌动物模型奠定了良好的基础。  相似文献   
108.
目的:寻找番荔枝科假鹰爪属植物假鹰爪Desmos chinensis抗肿瘤活性成分。方法:采用硅胶柱色谱分离化学成分。根据理化性质及波谱分析等方法鉴定结构。结果:从氯仿萃取物中分离鉴定了7个化合物,分别是unon-al(Ⅰ),黄芩素-7-甲醚(Ⅱ),去甲氧杜鹃花素(Ⅲ),去甲氧杜鹃花素-7-甲醚(Ⅳ),苯甲酸(Ⅴ),β-谷甾醇(Ⅵ)和豆甾醇(Ⅶ)。结论:该种植中鉴定的黄酮类化合物均为β-环未取代,  相似文献   
109.
The GNAS locus is an imprinted site. The α-subunit of the stimulatory G protein (Gsα) and extralarge variant (XLαs) are the two important products of the GNAS locus. The abnormal expression of Gsα is associated with pseudohypoparathyroidism (PHP) and related disorders, including Albright hereditary osteodystrophy (AHO), pseudopseudohypoparathyroidism (PPHP), and progressive osseous heteroplasia (POH). XLαs protein can mimic the catalytic intracellular synthesis of cyclic adenosine monophosphate (cAMP) by Gsα in response to parathyroid hormone (PTH) stimulation, which may be involved in the pathogenesis of PPHP and POH in patients with paternal GNAS defects. A paternally inherited nonsense variant in the first exon of XLαs in an adult patient may be associated with fractures and osteopetrosis. The relationship between the XLαs product of the GNAS locus and bone remodeling may have been overlooked. Here, we summarize the phenotypes of genetic mouse models and clinical cases of XLαs variations and suggest that the abnormal paternal expression of XLαs may be associated with the development of POH and affect osteoblast and osteoclast differentiation.  相似文献   
110.
The poly(l -lactic acid) (PLLA)/carbon nanomaterials composite foams with hierarchical surface microstructural and internal conductive pathways are successfully prepared by a simple crystallization-assisted rapid phase separation (CARPS). The dimension and morphology of carbon nanomaterials can induce different crystallization forms to construct the hierarchical surface microstructure, and they are distributed on the phase interface of solvent and non-solvent to form conductive pathways. It is found that the heterogeneous nucleation of nanomaterials promotes a significant increase in crystallinity, and a stacked granular structure formed on the surface promotes the increase of the water contact angle to 148.7°. Foams with interconnecting pore structures contribute to the formation of 85.3% porosity and 12.33 g g−1 oil absorption. Carbon nanomaterials are distributed on the pore walls of the porous foam, which converts the foam from an insulating material to a conducting polymer. Furthermore, the uniform distribution of nanomaterials significantly affects the thermal stability of the PLLA. In belief, the multifunctional biodegradable foam, prepared by a CARPS method, makes it promising for industrial production and has potential applications in electrical conductivity, oil-water separation, and many other fields.  相似文献   
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