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991.
Qian Yongjun Shao Huanzhang Zhou Wenxia Tang Hong Xiao Xijun 《Cardiovascular pathology》2013,22(3):211-218
BackgroundThe prevalence of atrial fibrillation (AF) and the frequency cardioversion of AF postoperatively are different in different forms of mitral valve disease. We hypothesized that these differences would relate to different extent of histopathological characteristics and oxidative injury in different forms of mitral valve diseases.MethodsLeft atrial appendages were obtained from 24 patients of mitral valve disease with or without AF undergoing mitral valve surgery. Control data were obtained from left appendages of 4 persons in normal sinus rhythm (SR) died of traffic accident. Histopathology, immunohistochemistry, Western blotting and enzyme kinetics examination were performed to assess the extent of histopathological characteristics and oxidative injury.ResultsThe average cross-sectional diameter of atrial myocyte of mitral stenosis (MS)+AF, MS+SR, mitral regurgitation (MR)+AF, MR+SR and control was 25.62±7.56 μm, 20.20±9.34 μm, 21.69±7.00 μm, 13.93±4.32 μm and 9.81±2.34 μm, respectively. Significantly statistical difference was found between each group (P<.05).Increased degree of atrial interstitial fibrosis was seen both in MS and MR with AF patients compared to other groups (P<.05), and the extent of fibrosis was more remarkable in MR patients compared to MS patients (P<.05).The extent of 3-nitrotyrosine (3-NT) immunoreactivity significantly increased in the patients with MS and AF compared to those of MR and AF (P<.05), and the immunoprevalence of 3-NT was significantly increased in patients of MS and SR compared to those of MR and SR (P<.05). Correlation analysis demonstrated a negative correlation between creatine kinase (CK) activity and extent of 3-NT immunoreactivity in atrial tissues (r=?0.382, P<.05).Significant decreases in CK activity were observed in myocardium from all patients of mitral valve disease with or without AF compared to controls (P<.05).Western blotting demonstrating an increased prevalence of 3-NT formation in CK-MM was detected compared to control group (P<.05). Correlation analysis demonstrated a negative correlation between CK-MM activity and extent of CK-MM tyrosine nitration (r=?0.446, P<.05).ConclusionsIn different forms of mitral valve disease with different cardiac rhythm, the extent of histopathological characteristics and oxidative injury are different. Histopathological characteristics and oxidative injury not only relate to mitral valve disease but also relate to the development and sustain of AF. 相似文献
992.
Outlet tube models incorporating a linearly flow-dependent resistance are widely used in pulsatile and rotary pump studies. The resistance is made up of a flow-proportional term and a constant term. Previous studies often focused on the steady state properties of the model. In this paper, a dynamic modeling procedure was presented. Model parameters were estimated by an unscented Kalman filter (UKF). The subspace model identification (SMI) algorithm was proposed to initialize the UKF. Model order and structure were also validated by SMI. A mock circulatory loop driven by a pneumatic pulsatile pump was developed to produce pulsatile pressure and flow. Hydraulic parameters of the outlet tube were adjusted manually by a clamp. Seven groups of steady state experiments were carried out to calibrate the flow-dependent resistance as reference values. Dynamic estimation results showed that the inertance estimates are insensitive to model structures. If the constant term was ignored, estimation errors for the flow-proportional term were limited within 16% of the reference values. Compared with the constant resistance, a time-varying one improves model accuracy in terms of root mean square error. The maximum improvement is up to 35%. However, including the constant term in the time-varying resistance will lead to serious estimation errors. 相似文献
993.
Bin Zhang Ke Yi Li Hai Ying Chen Shao Dong Pan Shuang Feng Chen Wei Feng Zhang Chun Peng Xia Li Cheng Jiang Xian Bin Liu Feng Jun Zhao Dao Ying Yuan Le Xin Wang Ya Ping Wu Shu Wei Liu 《International journal of medical sciences》2013,10(10):1301-1306
Background: The Nemo-like kinase (NLK) is a serine/threonine-protein kinase that involved in a number of signaling pathways regulating cell fate. Variation of NLK has been shown to be associated with the risk of cancer. However, the function of NLK in oral adenosquamous carcinoma cells line CAL-27 is unknown.Methods: In this study, we evaluated the function of NLK in CAL-27 cells by using lentivirus-mediated RNA silence. The targeted gene expression, cell proliferation and cell cycle are investigated by RT-PCR, western-blot, MTT method, colony forming assay and flow cytometry analysis respectively.Results: After NLK silencing, the number of colonies was significantly reduced (54±5 colonies/well compared with 262±18 colonies/well in non-infected or 226±4 colonies/well in negative control group (sequence not related to NLK sequence with mismatched bases). Using crystal violet staining, we also found that the cell number per colony was dramatically reduced. The RNA silencing of NLK blocks the G0/G1 phase to S phase progression during the cell cycle.Conclusions: These results suggest that NLK silencing by lentivirus-mediated RNA interference would be a potential therapeutic method to control oral squamous carcinoma growth. 相似文献
994.
Huan Li Yanan Wang Yutaro Aoki Saki Nishiyama Xiaofan Yang Tomoya Taguchi Akari Miura Ai Suzuki Lei Zhi Hidenori Goto Ritsuko Eguchi Takashi Kambe Yen-Fa Liao Hirofumi Ishii Yoshihiro Kubozono 《RSC advances》2020,10(45):26686
A superconducting KBi2 sample was successfully prepared using a liquid ammonia (NH3) technique. The temperature dependence of the magnetic susceptibility (M/H) showed a superconducting transition temperature (Tc) as high as 3.6 K. In addition, the shielding fraction at 2.0 K was evaluated to be 87%, i.e., a bulk superconductor was realized using the above method. The Tc value was the same as that reported for the KBi2 sample prepared using a high-temperature annealing method. An X-ray diffraction pattern measured based on the synchrotron X-ray radiation was analyzed using the Rietveld method, with a lattice constant, a, of 9.5010(1) Å under the space group of Fdm (face-centered cubic, no. 227). The lattice constant and space group found for the KBi2 sample using a liquid NH3 technique were the same as those reported for KBi2 through a high-temperature annealing method. Thus, the superconducting behavior and crystal structure of the KBi2 sample obtained in this study are almost the same as those for the KBi2 sample reported previously. Strictly speaking, the magnetic behavior of the superconductivity was different from that of a KBi2 sample reported previously, i.e., the KBi2 sample prepared using a liquid NH3 technique was a type-II like superconductor, contrary to that prepared using a high-temperature annealing method, the reason for which is fully discussed. These results indicate that the liquid NH3 technique is effective and simple for the preparation of a superconducting KBi2. In addition, the topological nature of the superconductivity for KBi2 was not confirmed.A superconducting KBi2 sample was successfully prepared using a liquid ammonia (NH3) technique. 相似文献
995.
In this review, we summarize the application of porphyrins and phthalocyanines in perovskite solar cells to date. Since the first porphyrin- and phthalocyanine-based perovskite solar cells were reported in 2009, their power conversion efficiency has dramatically increased from 3.9% to over 20%. Porphyrins and phthalocyanines have mostly been used as the charge selective layers in these cells. In some cases, they have been used inside the perovskite photoactive layer to form two-dimensional perovskite structures. In other cases, they were used at the interface to engineer the surface energy level. This review gives a chronological introduction to the application of porphyrins and phthalocyanines for perovskite solar cells depending on their role. This review article also provides the history of porphyrin and phthalocyanine derivative development from the perspective of perovskite solar cell applications.In this review, we summarize the application of porphyrins and phthalocyanines in perovskite solar cells to date. 相似文献
996.
Application of hyperspectral imaging for spatial prediction of soluble solid content in sweet potato
Yuanyuan Shao Yi Liu Guantao Xuan Yongxian Wang Zongmei Gao Zhichao Hu Xiang Han Chong Gao Kaili Wang 《RSC advances》2020,10(55):33148
Visible and near infrared (Vis-NIR) hyperspectral imaging was used for fast detection and visualization of soluble solid content (SSC) in ‘Beijing 553’ and ‘Red Banana’ sweet potatoes. Hyperspectral images were acquired from 420 ROIs of each cultivar of sliced sweet potatoes. There were 8 and 10 outliers removed from ‘Beijing 553’ and ‘Red Banana’ sweet potatoes by Monte Carlo partial least squares (MCPLS). The optimal spectral pretreatments were determined to enhance the performance of the prediction model. Successive projections algorithm (SPA) and competitive adaptive reweighted sampling (CARS) were employed to select characteristic wavelengths. SSC prediction models were developed using partial least squares regression (PLSR), support vector regression (SVR) and multivariate linear regression (MLR). The more effective prediction performances emerged from the SPA–SVR model with Rp2 of 0.8581, RMSEP of 0.2951 and RPDp of 2.56 for ‘Beijing 553’ sweet potato, and the CARS–MLR model with Rp2 of 0.8153, RMSEP of 0.2744 and RPDp of 2.09 for ‘Red Banana’ sweet potato. Spatial distribution maps of SSC were obtained in a pixel-wise manner using SPA–SVR and CARS–MLR models for quantifying the SSC level in a simple way. The overall results illustrated that Vis-NIR hyperspectral imaging was a powerful tool for spatial prediction of SSC in sweet potatoes.Visible and near infrared (Vis-NIR) hyperspectral imaging was used for fast detection and visualization of soluble solid content (SSC) in ‘Beijing 553’ and ‘Red Banana’ sweet potatoes. 相似文献
997.
998.
999.
Yang Fan Gao Yuxuan Zhang Lan Zheng Bo Wang Liu Sun Huan Huang Dingming 《Clinical oral investigations》2020,24(11):3781-3800
Clinical Oral Investigations - Pain management for the extraction of the mandibular third molar is a challenge as compelling evidence in comparative anaesthetics is currently lacking. Thorough... 相似文献
1000.
目的比较数字化改良囊腔塞治器与传统基托式囊肿塞治器在下颌骨囊肿开窗减压术后的临床运用及治疗效果。方法选取下颌骨囊肿开窗减压术后病例37例,随机分为数字化改良囊腔塞治器组和传统基托式囊肿塞治器组,对比两组所用塞治器的技工制作和临床操作用时、戴用后满意度评分及12个月后囊腔大小变化差异。结果数字化改良囊腔塞治器组塞治器的技工制作和临床操作平均用时与传统基托式囊肿塞治器组差异具有统计学意义(P=0.00);数字化改良囊腔塞治器组戴用塞治器后舒适度及清洁度的满意度评分与传统基托式囊肿塞治器组差异具有统计学意义(P<0.05),但两组对固位的满意度评分差异无统计学意义(P>0.05);数字化改良囊腔塞治器组与传统基托式囊肿塞治器组戴用塞治器12个月后囊腔明显减小,但两组间差异无统计学意义(P>0.05)。结论下颌骨囊肿开窗减压术后运用数字化改良囊腔塞治器和传统基托式囊肿塞治器均可取得良好的效果;数字化改良囊腔塞治器具有较高的时效性,患者满意度高,可作为下颌骨开窗减压术后的一种优选治疗装置。 相似文献