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81.
目的 体外合成针对人环氧化酶-2(hCOX-2)的小分子干扰RNA(siRNA),并转染人人滑膜成纤维细胞,通过比较不同siRNA抑制COX-2 mRNA表达、COX-2蛋白合成以及下游产物PGE2水平,旨在确定特异性阻断人滑膜成纤维细胞COX-2的siRNA.方法 分离、培养和传代人类风湿关节炎(类风关)滑膜成纤维细胞.设计合成4条针对hCOX-2 mRNA siRNA(1#-4#siRNA),1条随机序列siRNA.设立1#-4#siRNA和随机序列siRNA组(NC)及未转染对照组(CTL组).应用Lipofect AMINE 2000将上述siRNA分别转染人滑膜成纤维细胞,4 h后各培养孔加入终浓度为100 nmol/L的佛波酯.转染36 h、48 h后,各组提取蛋白质和总RNA,应用RT-PCR检测hCOX-2 mRNA表达水平,通过Western Blot检测hCOX-2蛋白表达水平.采用ELISA方法检测各组上清液PGE2的水平.结果 转染36 h,PCR结果显示,CTL、NC、1#siRNA、2#RNA、3#RNA、4#siRNA、阳性对照HeLa细胞组hCOX-2 mRNA电泳条带密度值分别为1、0.72、0.3、0.25、0.4、0.04、2.1.Western Blot结果提示上述各组hCOX-2蛋白密度值分别为1、1.04、0.52、0.39、0.9、0和2.48.转染48 h后,各组hCOX-2蛋白条带密度值分别为0.05、0.52、0.51、0.9和0.15.转染24 h、48 h和72 h后,4#siRNA组培养上清液PGE2的水平较其他各组低.结论 4#siRNA能有效抑制人滑膜成纤维细胞COX-2 mRNA表达和COX-2蛋白的合成,且上清液中PGE2水平最低,证实4#siRNA能特异性阻断COX-2在滑膜成纤维细胞表达.  相似文献   
82.
BackgroundThere is lack of studies on sequential regorafenib after sorafenib and lenvatinib treatment failure in patients with unresectable hepatocellular carcinoma (HCC). This study was to explore the safety and prognosis of sequential regorafenib after sorafenib and lenvatinib failure in HCC patients.MethodsThis study was a retrospective, real-world study that included 50 HCC patients who received sequential regrafinib after sorafenib and lenvatinib failure. The safety and prognosis of two groups were compared.ResultsThe incidence of all grade and III/IV adverse events were 68% and 24%. According to Response Evaluation Criteria in Solid Tumours (RECIST) 1.1 and modified (m) RECIST standards, the objective response rates (ORRs) after receiving regorafenib were 14.0% and 22.0%, respectively. The disease control rates (DCRs) were 62.0% and 60.0%, respectively. Based on different first-line targeted drugs, 50 patients were divided into sorafenib (n=22) and lenvatinib group (n=28). There was no differences between two groups except age and bilirubin. And there was no differences in other treatments before or after regorafenib. The baseline between two groups was basically same and had good comparability. There was no difference in incidence of all grade and III/IV adverse events, ORR and DCR between two groups (P>0.05). On long-term prognosis, total overall survival (TOS) in sorafenib and lenvatinib group were 23.0 (95% CI: 15.1–30.9) vs. 29.7 (95% CI: 21.4–38.1) months. The difference was statistically significant (P=0.041). Besides, regorafenib overall survival (ROS) in sorafenib and lenvatinib group were 11.7 (95% CI: 7.1–16.3) vs. 15.9 (95% CI: 8.3–23.5) months. The difference was statistically significant ( P=0.045). The regorafenib progression-free survival (RPFS) was 5.6 (95% CI: 1.9–9.2) vs. 8.0 (95% CI: 5.1–10.9) months in sorafenib and lenvatinib group, respectively, and difference was not statistically significant (P=0.380).ConclusionsRegorafenib is an effective drug for second-line treatment of HCC, with fewer severe adverse events, ORR and DCR was 14–22% and 62–60%, respectively. Both TOS and ROS in lenvatinib group were better than those in sorafenib group. For HCC patients whose first-line targeted drug is lenvatinib, it is safe and effective to accept regorafenib after disease progresses.  相似文献   
83.
Coronavirus disease 2019 (COVID-19) was first detected in China in December 2019, and declared as a pandemic by the World Health Organization (WHO) on March 11, 2020.To study the clinical features of patients with COVID-19, we analyzed the correlation between some inflammation-related indicators in patients’ serum and the severity of the disease, especially PV (pneumonia volume under CT scan) and pneumonia volume ratio (PVR).Sixty-six COVID-19 patients in Huai’an, China were selected as the research subjects. We collected the clinical data, including general characteristics, clinical symptoms, serum test results and CT performance, explored the relationship between inflammation-related indexes, oxygenation index, PV, PVR, while indicators of mild to moderate patients and severe patients were compared.The most prominent manifestations of COVID-19 patients were fever (47, 71.2%); cough (41, 62.1%), with or without respiratory and other systemic symptoms; There was no difference in gender (P = .567) and age (P = .865) between mild to moderate and severe groups. High sensitivity C-reactive protein (hs-CRP), erythrocyte sedimentation rate (ESR), and interleukin-6 (IL-6) of overall patients were higher than the normal range (P < .001, respectively). hs-CRP was negatively correlated with oxygenation index (OI) (r = –0.55), whereas positively correlated with PV, PVR and ESR (r = 0.89; r = 0.87; r = 0.47, respectively); ESR was negatively correlated with OI (r = –0.45), meanwhile it was positively correlated with PV and PVR (r = 0.44; r = 0.46, respectively). OI was negatively correlated with PV and PVR (r = –0.6, respectively). PV had a clear correlation with PVR (r = 1). Severe patients’ hs-CRP, PV, PVR were higher than mild to moderate group (P = .006; P = .001; P < .001, respectively), but OI was lower (P < .001).The clinical features of COVID-19 were similar to general viral pneumonia. hs-CRP, ESR showed a certain correlation with the PV and PVR, which might play a certain role in assessing the severity of COVID-19.  相似文献   
84.
Objectives:It is crucial to identify effective diagnostic biosignatures of tuberculosis (TB) to optimize its treatment. Herein, we conducted a systematic review to elucidate the diagnostic efficacy of long noncoding RNA (lncRNAs) as TB biomarkers.Methods:We searched Medline, Web of Science, Embase, Cochrane Library, CNKI, Wanfang, VIP, and China Biology Medicine disc databases up to February 18, 2020. These studies focusing on lncRNAs as diagnosis markers of TB were collected. STATA 12.0 and Meta-disc1.4 software were used to analyze the data extracted from eligible studies.Results:We included 8 articles with 1058 TB patients, and 1896 healthy controls in our study. The values of pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were 0.63, 0.86, 4.48, 0.43, and 10.31, respectively. Additionally, we plotted the summary receiver operating characteristic curve to evaluate the diagnostic accuracy, and the area under the curve was 0.80.Conclusion:The present study is the first meta-analysis to assess the diagnostic accuracy of lncRNAs in TB patients. We found that lncRNAs might constitute potential biomarkers for the diagnosis of TB patients. More population-based high-quality research should be conducted to validate the efficacy lncRNAs in TB patients.  相似文献   
85.
PurposeTerlipressin improves renal function in patients with septic shock. However, the mechanism remains unclear. Here, we aimed to evaluate the effects of terlipressin on renal perfusion in patients with septic shock.Materials and MethodsThis pilot study enrolled patients with septic shock in the intensive care unit of the tertiary hospital from September 2019 to May 2020. We randomly assigned patients to terlipressin and usual care groups using a 1:1 ratio. Terlipressin was intravenously pumped at a rate of 1.3 μg/kg/hour for 24 h. We monitored renal perfusion using renal contrast-enhanced ultrasound (CEUS). The primary outcome was peak sonographic signal intensity (a renal perfusion parameter monitored by CEUS) at 24 h after enrollment.Results22 patients were enrolled in this study with 10 in the terlipressin group and 12 in the usual care group. The baseline characteristics of patients between the two groups were comparable. The peak sonographic signal intensity at 24 h after enrollment in the terlipressin group (60.5 ± 8.6 dB) was significantly higher than that in the usual care group (52.4 ± 7.0 dB; mean difference, 7.1 dB; 95% CI, 0.4–13.9; adjusted p = .04). Patients in the terlipressin group had a lower time to peak, heart rates, norepinephrine dose, and a higher stroke volume at 24 h after enrollment. No significant difference in the urine output within 24 h and incidence of acute kidney injury within 28 days was found between the two groups.ConclusionsTerlipressin improves renal perfusion, increases stroke volume, and decreases norepinephrine dose and heart rates in patients with septic shock.  相似文献   
86.
Cardiovascular disease (CVD) is a group of diseases affecting the heart and blood vessels and is the leading cause of morbidity and mortality worldwide. Increasingly more evidence has shown that the senescence of vascular endothelial cells is the key to endothelial dysfunction and cardiovascular diseases. Anthocyanin is a type of water-soluble polyphenol pigment and secondary metabolite of plant-based food widely existing in fruits and vegetables. The gut microbiome is involved in the metabolism of anthocyanins and mediates the biological activities of anthocyanins and their metabolites, while anthocyanins also regulate the growth of specific bacteria in the microbiota and promote the proliferation of healthy anaerobic flora. Accumulating studies have shown that anthocyanins have antioxidant, anti-inflammatory, and anti-aging effects. Many animal and in vitro experiments have also proven that anthocyanins have protective effects on cardiovascular-disease-related dysfunction. However, the molecular mechanism of anthocyanin in eliminating aging endothelial cells and preventing cardiovascular diseases is very complex and is not fully understood. In this systematic review, we summarize the metabolism and activities of anthocyanins, as well as their effects on scavenging senescent cells and cardioprotection.  相似文献   
87.
目的建立流感茶的质量标准。方法采用薄层色谱法对处方中厚朴、槟榔、广藿香进行定性鉴别。结果薄层色谱中检出厚朴、槟榔、广藿香。结论本方法可行,重现性好,适用于该制剂的质量控制。  相似文献   
88.
SignificanceLine-field confocal optical coherence tomography (LC-OCT) is a recently introduced high-resolution imaging modality based on a combination of low-coherence optical interferometry and reflectance confocal optical microscopy with line illumination and line detection. Capable of producing three-dimensional (3D) images of the skin with cellular resolution, in vivo, LC-OCT has been mainly applied in dermatology and dermo-cosmetology. The LC-OCT devices capable of acquiring 3D images reported so far are based on a Linnik interferometer using two identical microscope objectives. In this configuration, LC-OCT cannot be designed to be a very compact and light device, and the image acquisition speed is limited.AimThe objective of this work was to develop a more compact and lighter LC-OCT device that is capable of acquiring images faster without significant degradation of the resolution and with optimized detection sensitivity.ApproachWe developed an LC-OCT device based on a Mirau interferometer using a single objective. Dynamic adjustment of the camera frequency during the depth scan is implemented, using a faster camera and a more powerful light source. The reflectivity of the beam-splitter in the Mirau interferometer was optimized to maximize the detection sensitivity. A galvanometer scanner was incorporated into the device for scanning the illumination line laterally. A stack of adjacent B-scans, constituting a 3D image, can thus be acquired.ResultsThe device is able to acquire and display B-scans at 17 fps. 3D images with a quasi-isotropic resolution of 1.5  μm (1.3, 1.9, and 1.1  μm in the x,y, and z directions, respectively) over a field of 940  μm×600  μm×350  μm (x×y×z) can be obtained. 3D imaging of human skin at cellular resolution, in vivo, is reported.ConclusionsThe acquisition rate of the B-scans, at 17 fps, is unprecedented in LC-OCT. Compared with the conventional LC-OCT devices based on a Linnik interferometer, the reported Mirau-based LC-OCT device can acquire B-scans 2 times faster. With potential advantages in terms of compactness and weight, a Mirau-based device could easily be integrated into a smaller and lighter handheld probe for use by dermatologists in their daily medical practice.  相似文献   
89.
90.
目的建立C57BL/6-gfp小鼠嗅球神经干细胞体外培养的方法,并初步应用于大鼠耳蜗核定位移植。方法培养C57BL/6-gfp小鼠胚胎嗅球神经千细胞,传代并进行分化实验及鉴定后将其立体定位注射于大鼠耳蜗核。结果所培养的神经干细胞生长良好,可稳定传代,能够分化为3种神经细胞。定位注射后可在局部见到绿色荧光阳性的细胞团。结论该方法培养的C57BL/6-gfp小鼠胚胎嗅球神经干细胞可稳定传代并可以作为荧光标记细胞进行移植实验。  相似文献   
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