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71.
With the development of coronary angiography for the diagnosis of coronary artery disease, its clinical significance in detecting coronary artery anomalies and evaluating the seriousness is attracting more attention. In the study we aimed to assess the prevalence of anomalous origin of coronary arteries in a Chinese population who underwent coronary angiography for coronary artery disease, and explore any patterns in the common variants and typical anomalies, especially the potentially serious ones. Patients who underwent coronary angiography from January 2013 to December 2016 in Fuwai Hospital were included. Baseline characteristics and angiographic data were collected, the incidence of anomalous origin of coronary arteries was calculated, and the typical patterns were analyzed. Comparisons between the present results and those of existing reports were also conducted. A total of 110,158 patients were included in the study, among which 0.76% (835 cases) had anomalous origin of coronary arteries. Among the anomalies, the incidences of anomalous origin of the right coronary artery (RCA), the left coronary artery (LCA), both the RCA and LCA, single coronary artery (SCA) and dextrocardia were 76.76% (641 cases), 14.61% (122 cases), 1.80% (15 cases), 4.67% (39 cases) and 2.16% (18 cases), respectively. Moreover, 47.54% (397 cases) of the anomalies were shown to be potentially serious, and an RCA arising from the left sinus of Valsalva (LSV) was the most common subtype (39.28%, 328 cases). Although anomalous origin of coronary arteries is not quite common, more clinical attention should be paid to this condition due to the potential risk of serious sequelae.  相似文献   
72.
按照高校教育教学改革微观系统工程研究理念,对北京中医药大学中药学院各专业学生开展问卷调查。通过SIMPP方法分析表明,学生通过对学习的自我准备、学习状态及学习效果提升,可以增强其对自主学习能力的认可度。从教师角度而言,采用因人而宜的个性化教学,可充分调动学生自学能力,进而促进大学教育中教与学二者的主动性,提高学生学习效率。  相似文献   
73.
74.
目的:探讨镍钛记忆合金环抱器治疗多发性肋骨骨折的疗效。方法100例多发性肋骨骨折患者均采用镍钛记忆合金环抱器行手术治疗。结果患者均无感染,骨折不愈合及内固定松动、滑脱等并发症发生;术后5个月~12个月取出内固定,骨折部位无炎症反应,心肺功能恢复较好。结论镍钛记忆合金环抱器呈现出良好的组织相容性,手术操作简便、创伤小、并发症少,是一种较为理想的治疗多发性肋骨骨折的方法。  相似文献   
75.
目的:研究皮鳞癌1号方对人皮肤鳞状癌A431细胞生长的抑制作用。方法:以0、5、10、20、40、80μg(生药)/ml皮鳞癌1号方分别作用A431细胞24、48、72 h后,测定光密度并计算细胞增殖抑制率以评价其抑制作用;在显微镜下观察细胞形态学变化;光化学法测定乳酸脱氢酶(LDH)的活性;免疫细胞化学法测定B淋巴细胞瘤2(Bcl-2)蛋白、Bcl-2相关X蛋白(Bax)的表达。结果:5、10、20、40、80μg(生药)/ml皮鳞癌1号方对A431细胞均有抑制作用(P<0.01);5、40μg(生药)/ml皮鳞癌1号方可使A431细胞增殖变缓,细胞出现皱缩,与周围细胞黏附力减弱;5、10、20μg(生药)/ml可明显增强A431细胞LDH活性、Bax表达,减弱Bcl-2表达,降低Bcl-2/Bax的比值(P<0.01)。结论:皮鳞癌1号方对A431细胞的增殖具有一定的抑制作用;可能与促进Bax表达、抑制Bcl-2表达、降低Bcl-2/Bax的比值有关。  相似文献   
76.
Shan  Dongkai  Wang  Xi  Dou  Guanhua  Zhang  Wei  Jing  Jing  He  Bai  Li  Yang  Chen  Yundai  Yang  Junjie 《Journal of thrombosis and thrombolysis》2021,51(4):915-923
Journal of Thrombosis and Thrombolysis - The relationship between vascular-specific epicardial adipose tissue (vEAT) volume and myocardial ischemia measured by fractional flow reserve (FFR) was not...  相似文献   
77.
目的 探讨大范围早期食管癌及其癌前病变内镜黏膜下剥离术(endoscopic submucosal dissection,ESD)术后发生食管顽固性狭窄的危险因素。方法 2013年7月—2017年12月,在中国医学科学院肿瘤医院内镜科行内镜黏膜下剥离术治疗,病变范围≥3/4食管环周的186例患者(共212处食管早期癌或癌前病变)纳入回顾性分析,根据术后内镜下食管球囊扩张次数分为顽固性狭窄组(69例,扩张≥6次)和非顽固性狭窄组(117例,扩张0~5次)。单因素分析使用t检验或Mann-Whitney U检验、χ2检验或Fisher精确概率法,多因素分析使用Logistic回归。结果 与非顽固性狭窄组比较,顽固性狭窄组在病变纵径、人工溃疡(ESD术后创面)纵径以及病变位置、病变环周范围和固有肌层损伤构成方面差异均有统计学意义(P均<0.05)。剔除人工溃疡纵径这一因素后(因人工溃疡纵径与病变纵径在临床上存在明显相关性),多因素Logistic回归分析结果显示,病变纵径>5 cm(P=0.003,OR=3.531,95%CI:1.547~8.060)、病变位于胸上段(与胸下段比较:P=0.001,OR=36.720,95%CI:4.233~318.551)、颈段(与胸下段比较:P=0.003,OR=24.959,95%CI:2.927~212.795)、全周病变(P<0.001,OR=10.082,95%CI:4.196~24.226)和存在术中固有肌层损伤(P<0.001,OR=7.128,95%CI:2.748~18.486)的早期食管癌及其癌前病变行ESD术后易发生食管顽固性狭窄。结论 对于大范围(病变范围≥3/4食管环周)早期食管癌及其癌前病变,病变纵径>5 cm,病变位于胸上段、颈段,全周病变,以及存在术中固有肌层损伤均是ESD术后发生食管顽固性狭窄的独立危险因素。  相似文献   
78.
Persons with advanced human immunodeficiency virus type one (HIV-1) infection seek medical advice for a wide range of neurological disorders including, but not limited to, peripheral neuropathy, toxoplasmosis, cryptococcal meningitis, cytomegalovirus retinitis progressive multifocal leukoencephalopathy, lymphoma and dementia. The diagnosis of HIV-1-associated dementia (HAD) induced as a direct consequence of HIV infection of the brain comes commonly by exclusion. Diagnostic decisions can often be clouded by concomitant depression, motor impairments, and lethargy that follow debilitating immune suppression and weight loss. Indeed, cognitive, motor and behavior abnormalities underlie a variety of neurological dysfunctions associated with advanced HIV-1 infection. Thus, even combinations of clinical, laboratory and neuroimaging tests [for example, magnetic resonance imaging (MRI), computed tomography (CT), single photon emission computed tomography (SPECT) and positron emission tomography (PET)] often fail to provide conclusive diagnostic information. Nonetheless, the recent development of quantitative MR spectroscopic imaging has improved diagnostic possibilities for HAD. We are pleased to discuss these developments as well as taking a forward look into what will soon be made available to improve neuroimaging diagnostic precision. New MR and SPECT testing are being developed in our laboratories and elsewhere both for animal model systems and in humans with HIV-1 disease. Such tests can facilitate dynamic measures of HIV-1 neuropathogenesis providing information for disease events that even 2 years ago were unattainable.  相似文献   
79.
Abstract

In this work, the expression of secreted frizzled related protein 2 (SFRP2) in rheumatoid arthritis (RA) model rats and the mechanisms of SFRP2 on the RA pathogenesis were investigated. Data suggested that SFRP2 was significantly down-regulated in RA model rats compared with normal control, and overexpression of SFRP2 suppressed the RA pathogenesis and the canonical Wnt signaling in fibroblast-like synovial cells (FLS) from RA model rats, whereas knockdown of SFRP2 got an opposite observation. Interestingly, 5-azadC treatment up-regulated the SFRP2 expression, inhibited the FLS proliferation, suppressed the expression of IL-6 and IL-8 and the fibronectin production, suggesting that the decreased SFRP2 in RA model rats was due to the DNA methylation. Furthermore, DNMT1 knockdown up-regulated the SFRP2 expression, DNMT1 overexpression inhibited the SFRP2, and the quantitative methylation-specific PCR (qMSP) confirmed that the DNMT1 has direct methylation roles for the SFRP2 promoter, leading to a regulation of FLS proliferation and fibronectin expression in RA model rats. In addition, up-regulated MeCP2 was involved in the SFRP2 regulation and the pathogenesis of RA model rats, and MeCP2 and DNMT1 have synergistic inhibition roles in the SFRP2 expression. Combination of DNMT1 and DNA methylation may be a promising treatment strategy for individuals with RA in which SFRP2 is down-regulated.  相似文献   
80.
Lung adenocarcinomas are usually sensitive to radiation therapy, but some develop resistance. Radiation resistance can lead to poor patient prognosis. Studies have shown that lung adenocarcinoma cells (H1299 cells) can develop radioresistance through epithelial-mesenchymal transition (EMT), and this process is regulated by miRNAs. However, it is unclear which miRNAs are involved in the process of EMT. In our present study, we found that miR-183 expression was increased in a radioresistant lung adenocarcinoma cell line (H1299R cells). We then explored the regulatory mechanism of miR-183 and found that it may be involved in the regulation of zinc finger E-box-binding homeobox 1 (ZEB1) expression and mediate EMT in lung adenocarcinoma cells. qPCR results showed that miR-183, ZEB1, and vimentin were highly expressed in H1299R cells, whereas no difference was observed in E-cadherin expression. Western blot results showed that ZEB1 and vimentin were highly expressed in H1299R cells, while E-cadherin expression was decreased. When miR-183 expression was inhibited in H1299R cells, radiation resistance, proliferation, and cell migration were decreased. The expression of ZEB1 and vimentin in H1299R cells was decreased, while the expression of E-cadherin was increased. Moreover, miR-183 overexpression in H1299 cells enhanced radiation resistance, proliferative capacity, and cell migration ability. The expression of ZEB1 and vimentin in H1299 cells was increased, while that of E-cadherin was decreased. In conclusion, miR-183 may promote EMT and radioresistance in H1299 cells, and targeting the miR-183-ZEB1 signaling pathway may be a promising approach for lung cancer treatment.  相似文献   
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