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991.
35岁女性因室上性心动过速行电生理检查和射频消融。术中诱发宽QRS心动过速,尝试心室超速起搏后变为窄QRS波,起搏后间期-心动过速周长为125 ms。仔细分析可发现两种心动过速周长和VA间期相同,希氏束呈现顺向夺获,校正后的起搏后间期-心动过速周长为75 ms。考虑顺向型房室折返性心动过速,于二尖瓣环左后间隔处消融成功。 相似文献
992.
This paper describes the development and validation of a liquid chromatography–mass spectrometric assay for propafenone and its application to a pharmacokinetic study of propafenone administered as a new propafenone hydrochloride sustained-release capsule (SR-test), as an instant-release tablet (IR-reference) and as the market leader sustained-release capsule (Rythmol, SR-reference) in male beagle dogs (n=8). In Study A comparing SR-test with IR-reference in a crossover design Tmax and t1/2 of propafenone for SR-test were significantly higher than those for IR-reference while Cmax and AUC were lower demonstrating the sustained release properties of the new formulation. In Study B comparing SR-test with SR-reference the observed Cmax and AUC of propafenone for SR-test (124.5±140.0 ng/mL and 612.0±699.2 ng·h/mL, respectively) were higher than for SR-reference (78.52±72.92 ng/mL and 423.6±431.6 ng·h/mL, respectively) although the differences were not significant. Overall, the new formulation has as good if not better sustained release characteristics to the market leader formulation.KEY WORDS: Propafenone, Pharmacokinetics, Sustained-release, Beagle dog, Plasma 相似文献
993.
Yunke Wang Shaozheng Hu Qiang Li Guizhou Gu Yanfeng Zhao Hongyu Liang Wei Li 《RSC advances》2018,8(64):36903
In this work, a two-component modified AgBr–Br–g-C3N4 composite catalyst with outstanding photocatalytic H2O2 production ability is synthesized. XRD, UV-Vis, N2 adsorption, TEM, XPS, EPR and PL were used to characterize the obtained catalysts. The as-prepared AgBr–Br–g-C3N4 composite catalyst shows the highest H2O2 equilibrium concentration of 3.9 mmol L−1, which is 7.8 and 19.5 times higher than that of GCN and AgBr. A “two channel pathway” is proposed for this reaction system which causes the remarkably promoted H2O2 production ability. In addition, compared with another two-component modified catalyst, Ag–AgBr–g-C3N4, AgBr–Br–g-C3N4 composite catalyst displays the higher photocatalytic H2O2 production ability and stability.In this work, a two-component modified AgBr–Br–g-C3N4 composite catalyst with outstanding photocatalytic H2O2 production ability is synthesized. 相似文献
994.
In the present study, aged refuse (AR) was modified to be applied as an adsorbent to remove humic acid from water. The efficiency of humic acid removal by modified aged refuse (MAR) under different preparation conditions (calcination temperature, dose of aged refuse for calcination and holding time) was systematically investigated. Results showed that the optimum preparation conditions are calcination temperature = 700 °C, AR dose for calcination = 25 g, and holding time = 2.0 h. The characteristics of the modified aged refuse obtained under different calcination conditions were determined by Fourier transform infrared, X-ray diffraction and X-ray photoelectron spectroscopy analysis. In addition, the effects of modified aged refuse dose and initial solution pH on adsorption performance were studied. The removal of humic acid increased with higher doses of modified aged refuse, and weak alkaline (initial pH = 8.0) conditions were favorable for humic acid removal. A pseudo-second order model fitted the experimental data well. Moreover, the adsorption isotherms were well described by the Langmuir isotherm model, in which the monolayer surface loading was calculated to be approximately 37 mg g−1. During the adsorption process, the molecular weight, degree of condensation and aromaticity of humic acid were considerably decreased, according to 3D-EEM analysis. MAR as a new type of adsorbent thus provides a potential adsorption method for humic acid.In the present study, aged refuse (AR) was modified to be applied as an adsorbent to remove humic acid from water. 相似文献
995.
Yanping Ruan Xiangyu Liu Haogang Zhu Yijie Lu Xiaowei Liu Jiancheng Han Lin Sun Ye Zhang Xiaoyan Gu Ying Zhao Lei Li Suzhen Ran Jingli Chen Qiong Yu Yan Xu Hongmei Xia Yihua He 《Congenital heart disease》2021,16(6):529-549
Background: Current studies have confirmed that fetal congenital heart diseases (CHDs) are caused by various factors. However, the quantitative risk of CHD is not clear given the combined effects of multiple factors. Objective: This cross-sectional study aimed to detect associated factors of fetal CHD using a Bayesian network in a large sample and quantitatively analyze relative risk ratios (RRs). Methods: Pregnant women who underwent fetal echocardiography (N = 16,086 including 3,312 with CHD fetuses) were analyzed. Twenty-six maternal and fetal factors were obtained. A Bayesian network is constructed based on all variables through structural learning and parameter learning methods to find the environmental factors that directly and indirectly associated with outcome, and the probability of fetal CHD in the two groups is predicted through a junction tree reasoning algorithm, so as to obtain RR for fetal CHD under different exposure factor combinations. Taking into account the effect of gestational week on the accuracy of model prediction, we conducted sensitivity analysis on gestational week groups. Results: The single-factor analysis showed that the RRs for the numbers of births, spontaneous abortions, and parental smoking were 1.50, 1.38, and 1.11 (P < 0.001), respectively. The risk gradually increased with the synergistic effect of ranging from one to more environmental factors above. The risk was higher among subjects with five synergistic factors, including the number of births, upper respiratory tract infection during early pregnancy, anemia, and mental stress as well as a history of spontaneous abortions or parental smoking, than in those with less than 5 factors (RR = 2.62 or 2.28, P < 0.001). This result was consistent across the participants grouped by GWs. Conclusion: We identified six factors that were directly associated with fetal CHD. A higher number of these factors led to a higher risk of CHD. These findings suggest that it is important to strengthen healthcare and prenatal counseling for women with these factors. 相似文献
996.
997.
Runmei Li Cong Cheng Zhuorui Wang Xuefan Gu Caixia Zhang Chen Wang Xinyue Liang Daodao Hu 《Materials》2021,14(2)
To verify the temperature sensitive failure of poly (N-isopropylacrylamide) (PNIPAM) anchored on the surface of gold nanoparticles (AuNPs), the UV-Vis spectra with temperature variations of the following aqueous solutions respectively containing AuNPs-PNIPAM, Au-PNIPAM/PNIPAM, PNIPAM, in different media (including salt, ethanol, HCl and cetyltrimethylammoniumbromide (CTAB)), were systematically determined. The results indicated that the UV-Vis spectrum of AuNPs-PNIPAM suspension hardly changed even above the Lower Critical Solution Temperature (LCST) of PNIPAM, but that of Au-PNIPAM/PNIPAM sharply increased only in absorbance intensity. A possible mechanism of the failed temperature sensitivity of PNIPAM anchored on the surface of AuNPs was proposed. Being different from free PNIPAM molecules, a strong interaction exists among PNIPAM molecules anchored on the surface of AuNPs, restraining the change in conformation of PNIPAM. The temperature sensitivity of Au-PNIPAM/PNIPAM originates from the free PNIPAM molecules rather than the anchored PNIPAM one. The changing electrostatic interaction could effectively regulate the aggregation behavior of AuNPs-PNIPAM and enhance its sensitivity to temperature. 相似文献
998.
Li Wang Zhen-yang Gu Shu-feng Liu De-xun Ma Chao Zhang Cheng-jun Liu Rui Gao Li-xun Guan Cheng-ying Zhu Fei-yan Wang Chun-ji Gao Hua-ping Wei 《Transfusion medicine reviews》2019,33(1):51-60
Controversial results exist regarding the clinical benefits of single- vs double-unit umbilical cord blood transplantation (UCBT) in patients with hematologic diseases. A systematic review was conducted to evaluate this issue. The PubMed, Embase, and Cochrane Library databases were searched up to May 2018. A total of 25 studies including 6571 recipients were identified. Although double-unit UCB contained higher doses of total nucleated cells and CD34+ cells, it offered no advantages over single-unit UCB in terms of hematologic recovery, including the rate and speed of neutrophil and platelet engraftment. Double-unit UCBT was associated with higher incidences of grades II-IV acute and extensive chronic graft-vs-host disease, accompanied by a lower relapse incidence, which may be attributed to a graft-vs-graft effect induced by double-unit UCB. However, transplant-related mortality, disease-free survival, and overall survival were comparable between single- and double-unit UCBT. Although double-unit UCBT confers no clinical advantages over single-unit UCBT, certain patients, such as those at high risk of relapse, might benefit from double-unit UCBT, a possibility that needs to be clarified in future randomized trials. 相似文献
999.
Oh Jae Gu Choi Seo-Youn Lee Min Hee Lee Ji Eun Yi Boem Ha Kim Seung Soo Min Ji Hye Lee Bora 《Abdominal imaging》2019,44(2):529-538
Abdominal Radiology - The objective of the study is to identify computed tomography (CT) findings that differentiate hepatic abscess from hepatic metastasis in a patient with a history of... 相似文献
1000.
Bo Pang MM Yonghuai Wang MD Shuang Liu MD PhD Jun Yang MD PhD Tianxiang Gu MD PhD Chunyan Ma MD PhD 《Journal of clinical ultrasound : JCU》2019,47(6):376-379
Barlow's disease is a complicated form of degenerative mitral valve (MV) disease. Infective endocarditis (IE) often occurs on the basis of primary heart diseases and may be combined with valve perforations. Cleft-like indentations (CLIs) were suggested by Ring et al. in 2013. They are located at the inter-scallop position and involve at least one-half of the valve. Herein, we report a case of Barlow's disease combined with IE and CLIs, which was confirmed intra-operatively and by histopathological examination. The CLIs were misdiagnosed by two-dimensional transthoracic echocardiography as perforations, but rightly interpreted by preoperative three-dimensional echocardiography. The possibility of CLIs should be considered in the evaluation of mitral regurgitation caused by myxomatous MV diseases. 相似文献