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41.
tRNA-derived fragments, a class of small noncoding RNAs (sncRNAs), have been identified in numerous studies in recent years. tRNA-derived fragments are classified into two main groups, including tRNA halves (tiRNAs) and tRNA-derived small RNA fragments (tRFs), according to different cleavage positions of the precursor or mature tRNAs. Instead of random tRNA degradation debris, a growing body of evidence has shown that tRNA-derived fragments are precise products of specific tRNA modifications and play important roles in biological activities, such as regulating protein translation, affecting gene expression, and altering immune signaling. Recently, the relations between tRNA-derived fragments and the occurrence of human diseases, especially cancers, have generated wide interest. It has been demonstrated that tRNA-derived fragments are involved in cancer cell proliferation, metastasis, progression and survival. In this review, we will describe the biogenesis of tRNA-derived fragments, the distinct expression and function of tRNA-derived fragments in the development of cancers, and their emerging roles as diagnostic and prognostic biomarkers and precise targets of future treatments.  相似文献   
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43.
Porocarcinoma is an unusual, locally aggressive and potentially fatal neoplasm. Several cutaneous malignancies have been described in association with porocarcinoma, including squamous cell carcinoma, basal cell carcinoma and tricholemmal carcinoma. Previous reports have indicated that the occurrence of malignant tumours in combination with porocarcinoma is extremely rare, in particular with regard to Bowen disease (BD). We report an uncommon case of porocarcinoma occurring synchronously in a single BD lesion in a 63‐year‐old woman with multiple BD lesions. The clinical and histological findings confirmed this diagnosis.  相似文献   
44.
目的探讨输尿管支架管结壳患者尿液菌群的分布特点。方法选取2018年10月至2019年3月在山东省立第三医院、山东大学齐鲁医院、济南市中心医院和济南市济钢医院就诊的35例输尿管支架管置入术后患者。纳入标准:年龄18~65岁;输尿管镜碎石术后留置内支架管4周。排除标准:尿液细菌培养阳性;严重肉眼血尿;近期口服抗生素;存在明显残石患者。本研究采用横断面研究方法(临床研究注册号为ChiCTR1800020025),根据有无支架管结壳将患者分为结壳组23例和无结壳组12例。收集拔管当日患者尿液行细菌16s DNA检测。使用UPARSE、UCHIME和RDP calssifier等软件分析两组患者尿液菌群分布特点,明确两组患者尿液中细菌种类总数、细菌丰度,以及丰度占比较大的细菌类别,比较两组患者尿液细菌种类、数量及细菌丰度的差异,明确结壳组患者尿液中丰度占比较大的细菌菌属。结果两组患者的年龄、性别、体质指数、置管侧别、内支架管型号及结石成分差异均无统计学意义(P>0.05)。16s DNA检测结果显示,结壳组丰度占比>1%的菌属数量为11个,丰度占比>0.01%的菌属数量为74个;无结壳组丰度占比>1%的菌属数量为7个,丰度占比>0.01%的菌属数量为11个,两组丰度占比>1%的菌属数量比较差异有统计学意义(t=5.12,P=0.000)。结壳组中菌属丰度占比前3位分别为乳杆菌属(23.1%)、拟杆菌属(18.8%)和未分级拟杆菌属(17.1%),非结壳组中菌属丰度占比前3位分别是为埃希菌-志贺菌属(32.2%)、肠球菌属(24.9%)和假单胞菌属(18.2%)。两组间差异最大的3种细菌是乳杆菌属(P=0.010),拟杆菌属(P=0.004)和未分级拟杆菌属(P=0.004)。结论支架管结壳患者尿液中细菌种类和数量都明显多于非支架管结壳患者。拟杆菌属细菌在支架管结壳患者尿液中的细菌种类丰度较大。  相似文献   
45.
Major ursodeoxycholic acid (UDCA)-based therapies for primary biliary cirrhosis (PBC) include UDCA only, or combined with either methotrexate (MTX), corticosteroids (COT), colchicine (COC), or bezafibrate (BEF). As the optimum treatment regimen is unclear and warrants exploration, we aimed to compare these therapies in terms of patient mortality or liver transplantation (MOLT) and adverse events (AE).PubMed, the Cochrane Library, and Scopus were searched for randomized controlled trials up to August 31, 2014. We estimated the hazard ratios (HRs) for MOLT and odds ratios (ORs) for AE. A sensitivity analysis based on the dose of UDCA was also executed.Thirty-one eligible articles were included. Compared with COT plus UDCA, UDCA (HR 0.38, 95% confidence interval [CI] 0.09–1.39), BEF plus UDCA (HR 0.29, 95% CI 0.02–4.83), COC plus UDCA (HR 0.39, 95% CI 0.07–2.25), MTX plus UDCA (HR 0.28, 95% CI 0.05–1.63), or OBS (HR 0.49, 95% CI 0.11–2.01) all provided an increased risk of MOLT. With respect to drug AE profile, although not differing appreciably, BEF plus UDCA was associated with more AEs compared with UDCA (OR 3.16, 95% CI 0.59–20.67), COT plus UDCA (OR 2.27, 95% CI 0.15–33.36), COC plus UDCA (OR 1.00, 95% CI 0.09–12.16), MTX plus UDCA (OR 2.03, 95% CI 0.23–17.82), or OBS (OR 3.00, 95% CI 0.53–20.75). The results of sensitivity analyses were highly consistent with previous analyses.COT plus UDCA was the optimal UDCA-based regimen for both MOLT and AEs. BEF plus UDCA was most likely to cause AEs, whereas monotherapy with UDCA and coadministriation of COT plus UDCA appeared to be associated with the fewest AEs for PBC treatment.  相似文献   
46.
Objective: To evaluate the effectiveness of a modified behavioral activation treatment (MBAT) intervention on reducing depressive symptoms in rural left-behind elderly.

Method: This is a randomized study registered in Chinese Clinical Trial Registry (ChiCTR-IOR-17011289). Eighty rural left-behind elderly people who had a Geriatric Depression Scale (GDS) score between 11 and 25 were randomly assigned to the intervention (n?=?40) and control group (n?=?40). The intervention group received both MBAT and regular treatment for 8 weeks while the control group received regular treatment. Both groups were assessed with the GDS, Beck Anxiety Inventory (BAI), and Oxford Happiness Questionnaire (OHQ) at baseline, immediately post-intervention, and at 3 months post-intervention.

Results: There were a total of 73 participants that completed the intervention. The scores of GDS and BAI decreased significantly, but the scores of OHQ increased significantly in the intervention group after 8 sessions of MBAT (P?<?.01). The reduction in depression symptoms after the intervention was maintained at the 3-month follow-up. Significant differences in GDS, BAI, and OHQ scores were observed between the intervention group and the control group (P?<?.01).

Conclusion: MBAT produced a significantly greater reduction in depressive symptoms than regular care in rural left-behind elderly.

Clinical or methodological significance of this article: A modified behavioral activation (BA) psychotherapy can significantly reduce the recurrence and seriousness of depression symptoms in the left-behind elderly with mild to moderate depression. This study also suggests that further study of the MBAT as an intervention will provide a direction for the management of mental health in rural left-behind elders.  相似文献   

47.
目的:分析宣威地区与非宣威地区的肺癌临床流行病学与病理特征。方法:以云南省肿瘤医院(昆明医科大学第三附属医院)2015年3月至2015年5月手术治疗的肺癌患者为研究对象,共295例,收集患者相关信息。将其分为宣威地区、非宣威地区进行统计。对患者的临床资料进行回顾性分析,包含病理类型、年龄、性别、吸烟史等。结果:宣威地区、非宣威地区肺癌患者男女比例为1.19∶1和1.69∶1。宣威地区患者平均年龄为[53.41±8.74(34~85)]岁,中位年龄53岁。非宣威地区肺癌患者平均年龄为[58.68±8.63(38~78)]岁,中位年龄59岁。宣威地区肺癌高发年龄为40~59岁段。宣威地区I期肺癌患者占比、T1期肺癌患者占比、N0期肺癌患者占比均高于非宣威地区。宣威地区男性腺癌鳞癌比远高于非宣威地区,差异有显著统计学意义。结论:宣威地区女性肺癌发病率更高,发病年龄更趋年轻化,腺癌比例高,吸烟与宣威地区男性腺癌高发关系不密切。  相似文献   
48.
49.
目的 利用MRI技术连续采集头颈部肿瘤患者吞咽时图像,观察并测量软腭、舌、喉的运动规律及最大活动度。方法 随机选取2018年7月-10月在中国医学科学院肿瘤医院接受调强放疗的原发头颈部恶性肿瘤20例患者,其中男17例、女3例,中位年龄58.5岁(28~78岁)。20例患者中鼻咽癌7例,口腔癌3例,口咽癌5例,下咽癌3例,鼻腔鼻旁窦2例。根据AJCC第八版分期Ⅰ-Ⅱ期患者2例,Ⅲ期8例,Ⅳ期10例。结果 吞咽时软腭向上移动移动距离为(1.06±0.31) cm且服从正态分布,向后移动距离为(0.83±0.24) cm且近似正态分布。舌体向后移动距离为(0.77±0.22) cm,且服从正态分布。含压舌板行图像采集患者舌上移位移为0,无压舌板患者舌体中位上移距离为1.23 cm (0.59~1.41 cm)。喉向上移动距离为(1.14±0.22) cm且服从正态分布,向前移动的中位距离为0.4 cm (0.27~0.90 cm)。结论 吞咽运动有可能发生于头颈部肿瘤患者放疗过程中,并引起大体肿瘤体积(GTV)及周围正常组织移动;因此在制定放疗计划时应注意GTV至PGTV的个体化外放距离,以保证肿瘤处方剂量。  相似文献   
50.
In China, colorectal cancer (CRC) ranked fourth and fifth in the highest incidence and mortality rates of all malignancies in 2018, respectively. Although these rates are below the world average, China placed first worldwide in the number of new CRC cases and CRC-related deaths because of its comparatively large population. This disease represents a threat to the health of population and incurs a heavy economic burden on the society and individuals. CRC has various risk factors, including age, sex, lifestyle, genetic factors, obesity, diabetes, gut microbiota status, and precancerous lesions. Furthermore, incidence and mortality rates of CRC are closely related to socioeconomic development levels, varying according to regional and population characteristics. Prevention is the main strategy to reduce incidence and mortality rates of CRC. This can be achieved through strategies stimulating lifestyle changes, healthy diet habits, and early screening for high-risk individuals. To reduce the burden of CRC, public health officials should promote prevention and management of modifiable risk factors through national policies. The rising incidence and mortality rates of CRC in China may be timely curbed by clarifying specific epidemiological characteristics, optimizing early screening strategies, and strictly implementing diagnosis and treatment guidelines. Thus, this study aimed to collect and report the current research status on epidemiology and risk factors of CRC in China.  相似文献   
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