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51.
刘青山姜晨荆涛任禹霏刘军刘勇 《现代生物医学进展》2012,12(12):2352-2355
目的:探讨国人前列腺癌患者前列腺体积与肿瘤分级之间的关系。方法:回顾我院及武汉大学人民医院2005年1月-2011年10月70例确诊为前列腺癌并行根治性前列腺切除术(RP)患者的临床病理资料,采用SPSS13.0软件总结并分析前列腺癌患者前列腺体积与肿瘤分级之间的关系。结果:经直肠前列腺穿刺活检获得肿瘤病理分级与根治性前列切除术获得最终病理分级具有显著差异(P=0.003);在活检及根治性前列腺切除标本中,前列腺体积与高级别肿瘤发生率均呈负相关(P<0.05);小前列腺与阳性手术切缘、前列腺外侵犯及高级别肿瘤在单变量分析中具有相关性(P<0.05),而与精囊腺侵犯及淋巴结侵犯则无相关性(P>0.05);在校正了年龄、体重指数及术前前列腺特异性抗原水平后,前列腺体积与阳性手术切缘、前列腺外侵犯、精囊腺侵犯及高级别肿瘤发生率均呈负相关(OR<1,P<0.05),而与淋巴结侵犯则无相关性(P>0.05)。结论:前列腺体积是高级别前列腺癌的重要预测因子,利用其对高级别肿瘤风险的预测能力可帮助选择最佳治疗方案并进一步提高治疗效果。 相似文献
52.
病理性瘢痕一直是整形外科乃至整个外科界研究的热点,由于其发病机制十分复杂,迄今尚无明确的病因学诊断和有效的治疗方法.VEGF作为目前活性最强的血管生长因子,与病理性瘢痕的发生、发展关系密切.研究病理性瘢痕形成过程中VEGF的表达及调控机制,有助于阐明病理性瘢痕的发病机制,为预防和治疗病理性瘢痕提供依据. 相似文献
53.
昆虫濒危等级和保护级别 总被引:3,自引:1,他引:2
介绍了国际上目前普遍通用的物种濒危等级系统“IUCN红色名录等级 ( 1994年版 )”来源和结构及使用注意事项 ,对我国 1989年公布生效的《国家重点保护野生动物名录》保护级别和昆虫收录情况进行了评介 ,最后就保护名录与红皮书或红色名录的关系及国家重点保护昆虫的遴选和定级原则提出讨论和建议 相似文献
54.
Carol J. Kelsey James Duffin 《European journal of applied physiology and occupational physiology》1992,65(5):480-484
These experiments examined the changes in ventilation during a 40-s ramp increase in exercise load, produced by increasing either the speed of the treadmill or the grade, to equivalent end-points of oxygen uptake. Six subjects underwent five trials each for grade and speed, while ventilation was monitored breath-by-breath. For each subject, ventilation versus time for all five of the speed trials was plotted on a single graph and fitted by linear regression. The data for the grade trials were similarly treated. For all subjects, the slope of the regression line for the speed plots was found to be significantly (P < 0.05) greater than that for the grade plots. We concluded that these experimental results support the hypothesis that the neural drive to ventilation persists as exercise continues and is proportionately related to the frequency of limb movement. 相似文献
55.
Chenyu Guan Daiqiao Ouyang Yongjie Qiao Kan Li Guangsen Zheng Xiaomei Lao Sien Zhang Guiqing Liao Yujie Liang 《Journal of cellular and molecular medicine》2020,24(10):5832-5841
CA9 is a member of the carbonic anhydrases’ family, that is often expressed in cancer cells under hypoxic condition. However, the role of CA9 in the molecular mechanisms of tongue squamous cell carcinoma (TSCC) pathogenesis remains unclear. CA9 expression was analysed using the TCGA database, and its influence on survival was performed using Kaplan-Meier, LASSO and COX regression analyses. The correlation between CA9 and immune infiltration was investigated by CIBERSORT and ESTIMATE. Moreover, the relationship between CA9 expression and downstream molecular regulation pathways was analysed by GSEA, GO and WGCNA. CA9 expression correlated with clinical prognosis and tumour grade in TSCC. Moreover, CA9 expression potentially contributes to the regulation of cancer cell differentiation and mediates tumour-associated genes and signalling pathways, including apoptosis, hypoxia, G2M checkpoint, PI3K/AKR/mTOR signalling and TGF-beta signalling pathways. However, the follicular helper T cells, regulatory T cells, immune and stromal scores showed no significance between high and low CA9 expression groups. These findings suggested that CA9 plays a critical role of TSCC prognosis and tumour grade. CA9 expression significantly correlated with the regulation of cell differentiation, various oncogenes and cancer-associated pathways. 相似文献
56.
More than a century has passed since pathological protein aggregates were first identified in the brains of patients with neurodegenerative diseases (NDDs). Yet, we still do not have effective therapies to treat or slow the progression of these devastating diseases or diagnostics for early detection and monitoring disease progression. Herein, I reflect on recent findings that are challenging traditional views about the composition, ultrastructural properties, and diversity of protein pathologies in the brain, their mechanisms of formation and how we investigate and model pathological aggregation processes in the laboratory today. This article is an invitation to embrace the complexity of proteinopathies as an essential step to understanding the molecular mechanisms underpinning NDDs and to advance translational research and drug discovery in NDDs. 相似文献
57.
Melissa Parks 《Science activities》2018,55(1-2):46-57
With school days seemingly getting shorter and packed with more and more obligations, teachers integrate core subjects like science and reading in the hopes of delivering a curriculum that is meaningful and content rich. Using trade books, primary teachers can develop and deliver science content designed to introduce students to proenvironmental behaviors built around the Next Generation Science Earth and Human Activity Standard, Human Impacts on Earth Systems, ESS3-C. The Next Generation Science standards call for integrating literacy skills and science to develop knowledge of scientific topics. This article shares ideas on how primary teachers can use a variety of children’s literature as a foundation to inspire young students to take small steps toward developing proenvironmental behaviors. Under an umbrella of three environmental themes, proenvironmental behavior, trash, and water pollution, the article describes key concepts, vocabulary, and activities designed to develop a mindfulness of proenvironmental behaviors for each selected text. While texts and learning experiences are intentionally focused on young learners (Kindergarten/first grade), they can be adapted and used in all primary grades. 相似文献
58.
从患者皮损处皮屑及活检组织中分离出的暗纹节菱孢Arthriniumphaeospermum(Corda)Ellis菌株制成混悬菌液,用兔、豚鼠及小鼠(LACA)进行动物毒理实验。表皮直接涂抹法接种,四周后未见皮肤损害;划破表皮涂沫法及皮下注射法接种,两周后实验动物的皮肤都出现浸润性斑块、小给节、皮下脓肿及脱毛的症状,对照组动物正常。再用腹腔注射法接种,小鼠两周后死亡,病解所见,腹膜、肠系膜、腹壁及肝等处,均出现散在的灰白色小脓肿;心、肺、肝、脾及肾均有病变。豚鼠两周后仍存活,当即处死解剖所见与小鼠病解改变相同。对实验动物皮损、腹膜、肠系膜、胃及肝等处的小脓肿组织进行了病理检查,结果发现皮损及器官组织均有明显的病理浸润,由多种细胞构成的浸润性肉芽肿。在病理浸润内可见大小不等的球形、卵圆形、棱形及晶体形的棕色、红色孢子.其病理改变与患者皮损病理改变相一致,其不同点是实验动物有小脓肿,肉芽肿内可见多核巨噬细胞,而在病人皮损中很少见到。 相似文献
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