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目的:研究结直肠癌(CRC)患者和健康人大肠组织中免疫细胞的浸润情况,为后续开展肿瘤微环境的研究提供前期的分析结果和数据。方法:通过GEO数据库对51例正常人结直肠组织和333例CRC患者肿瘤组织的基因表达谱数据进行计算分析,通过CIBERSORT方法将基因表达谱数据转化为组织中22种免疫细胞的浸润比例,对比这些免疫细胞在两者中的分布情况。结果:肠道浸润的免疫细胞组成在CRC患者与健康人之间有较大差异。T细胞和B细胞在肿瘤组织中的浸润数量少于健康人,而巨噬细胞、中性粒细胞、肥大细胞和树突状细胞在肿瘤组织中的浸润数量大于健康人。结论:CRC患者和健康人的结直肠组织中免疫细胞浸润存在较大的差异,这些具有差异的免疫细胞在癌症进展中可能发挥重要作用。  相似文献   
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目的:了解COVID-19疑似病房护理人员的压力状况,为缓解临床护理人员的压力提供参照。方法:采用现象学研究法,于2020 年2月2日至2020 年3月2日,对温州医科大学附属第二医院育英儿童医院8 名COVID-19疑似病房护理人员进行半结构式访谈,运用Colaizzi七步分析法对资料进行分析。结果:对疑似病房护理人员的压力可归纳出三个主题:工作压力,社会支持利用度减少,负性情绪难以排解。其中工作压力包含3 个次主题:负荷重、社会期待高、职业暴露。结论:COVID-19疑似病房护理人员存在多方面的工作压力,应加强人力资源配置优化管理,做好COVID-19相关知识宣传,及时更新防护措施及知识,加强人文关怀,缓解护理人员压力  相似文献   
65.

Backgroud

Cardiac-specific deletion of ALK3 is lethal in mid-gestation with ventricular septum malformations (VSM). This study was designed to define the Pax-8's role in heart development and cardiomyocyte apoptosis.

Methods

Pathologic changes in the hearts of Pax-8 or ALK3 knockout and wild type control mice were determined by light and electron microscopy. Analysis of cardiomyocyte apoptosis was performed by TUNEL. The effect of Pax-8 gene deficiency on caspase-3 activity was examined after transfecting Pax-8 siRNA into cultured myoblast cell line.

Results

Mice with ALK3 or Pax-8 gene knockout but not wild type control animals showed the development of VSM. Increased cardiomyocyte apoptosis was found in homozygotes. Echocardiography showed that Pax-8 homozygote mice developed malfunction of the heart. Furthermore, the caspase-3 activity was significantly higher in the cells treated with Pax-8 siRNA as compared to those treated with negative control siRNA in H9C2 (2-1) cell line.

Conclusions

The Pax-8 gene may play a crucial role in heart development and regulating cardiocyte apoptosis. Knockout of Pax-8 may exert a similar effect on myocardial morphology and apoptosis as those seen in ALK3 knockouts. Furthermore, the ventricular septum malformations could be partially attributed to accelerated cardiomyocyte apoptosis.  相似文献   
66.
选用冠心病介入治疗中常用的7个投照体位,在没有辐射防护情况下分别测量第一操作者在不同高度体表所受的入射剂量,并绘制体表入射剂量分布图。结果是重要辐射剂量区域内剂量峰值都出现在20~70 cm高度;在130~160cm高度出现剂量次高峰。投照体位以左脚位(spider位)时入射剂量最大。  相似文献   
67.
AIM: To investigate the mechanism of interleukin (IL)-6 secretion through blocking the IL-17A/IL-17A recepto (IL-17RA) signaling pathway with a short hairpin RNA (shRNA) in hepatic stellate cells (HSCs) in vitro . METHODS: HSCs were derived from the livers of adul male Sprague-Dawley rats. IL-6 expression was evalu ated using real-time quantitative polymerase chain reaction and enzyme linked immunosorbent assay. The phosphorylation activity of p38 mitogen activated pro tein kinases (MAPK) and extracellular regulated pro tein kinases (ERK) 1/2 upon induction by IL-17A and suppression by IL-17RA shRNA were examined using Western blotting.RESULTS: IL-6 expression induced by IL-17A was significantly increased compared to control in HSCs (P 0.01 in a dose-dependent manner). Suppression of IL17RA using lentiviral-mediated shRNA inhibited IL-6 expression induced by IL-17A compared to group with only IL-17A treatment (1.44 ± 0.17 vs 4.07 ± 0.43, P 0.01). IL-17A induced rapid phosphorylation of p38 MAPK and ERK1/2 after 5 min exposure, and showed the strongest levels of phosphorylation of p38 MAPK and ERK1/2 at 15 min in IL-17A-treated HSCs. IL-6 mRNA expression induced by IL-17A (100 ng/mL) for 3 h exposure was inhibited by preincubation with specific inhibitors of p38 MAPK (SB-203580) and ERK1/2 (PD-98059) compared to groups without inhibitors preincubation (1.67 ± 0.24, 2.01 ± 0.10 vs 4.08 ± 0.59, P 0.01). Moreover, lentiviral-mediated IL-17RA shRNA 1 inhibited IL-17A-induced IL-6 mRNA expression compared to random shRNA in HSCs (1.44 ± 0.17 vs 3.98 ± 0.68, P 0.01). Lentiviral-mediated IL17RA shRNA 1 inhibited phosphorylation of p38 MAPK and ERK1/2 induced by 15 min IL-17A (100 ng/mL) exposure. CONCLUSION: Down-regulation of the IL-17RA receptor by shRNA decreased IL-6 expression induced by IL-17A via p38 MAPK and ERK1/2 phosphorylation in HSCs. Suppression of IL-17RA expression may be a strategy to reduce the inflammatory response induced by IL-17A in the liver.  相似文献   
68.
The early identification of toxic paraquat (PQ) poisoning in patients is critical to ensure timely and accurate prognosis. Although plasma PQ concentration has been reported as a clinical indicator of PQ poisoning, it is not commonly applied in practice due to the inconvenient necessary instruments and operation. In this study, we explored the use of blood routine indexes to identify the degree of PQ toxicity and/or diagnose PQ poisoning in patients via machine learning approach. Specifically, we developed a method based on support vector machine combined with the feature selection technique to accurately predict PQ poisoning risk status, then tested the method on 79 (42 male and 37 female; 41 living and 38 deceased) patients. The detection method was rigorously evaluated against a real‐world data set to determine its accuracy, sensitivity and specificity. Feature selection was also applied to identify the factors correlated with risk status, and the results showed that there are significant differences in blood routine indexes between dead and living PQ‐poisoned individuals (p‐value < 0.01). Feature selection also showed that the most important correlated indexes are white blood cell and neutrophils. In conclusion, the toxicity or prognosis of PQ poisoning can be preliminarily ascertained by blood routine testing without PQ concentration data, representing an additional tool and innovative approach to assess the prognosis of PQ poisoning.  相似文献   
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70.
目的 评价普瑞巴林添加治疗部分性癫(癎)发作的疗效和安全性.方法采用随机、双盲、安慰剂对照、多中心平行设计添加治疗的方法,确诊为有部分性癫(癎)发作的225例癫(癎)患者,被随机分配入普瑞巴林治疗组(114例)与安慰剂组(111例).在6周前瞻性基线期后,采用灵活剂量的普瑞巴林(150~600 mg·d-1)添加治疗成人部分性癫(癎)发作.主要疗效指标:部分性癫(癎)发作28 d-反应率.次要疗效指标:部分性癫(癎)发作28d-减少率、临床疗效评价、16周内癫(癎)无发作和发作减少率≥50%的病例比例、第13~16周癫(癎)无发作和发作减少率≥50%的病例比例以及临床疗效总评量表评分;并观察研究药物的安全性与不良反应情况.结果 普瑞巴林组部分性癫(癎)发作28 d-反应率(-40.24±37.88)%,显著高于安慰剂组(-22.84±37.61)%(F=15.063 9,P=0.000 l).普瑞巴林组和安慰剂组的不良事件发生率分别为60.53%和47.75%,组间无显著差异;但普瑞巴林组的不良反应发生率较安慰剂组高(45.61% vs 23.42%,P=0.000 7),主要不良反应有头晕、嗜睡、视物模糊、乏力等.结论 普瑞巴林组的疗效显著优于安慰剂组.普瑞巴林作为部分性癫(痈)发作的添加药物有确定的疗效,安全耐受性较好,具有一定临床应用价值.  相似文献   
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