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991.
Luigi Yuri Di Marco Costanzo Di Maria Wing-Chiu Tong Michael J. Taggart Stephen C. Robson Philip Langley 《Medical & biological engineering & computing》2014,52(8):707-716
Abdominal uterine electromyograms (uEMG) studies have focused on uterine contractions to describe the evolution of uterine activity and preterm birth (PTB) prediction. Stationary, non-contracting uEMG has not been studied. The aim of the study was to investigate the recurring patterns in stationary uEMG, their relationship with gestation age and PTB, and PTB predictivity. A public database of 300 (38 PTB) three-channel (S1–S3) uEMG recordings of 30 min, collected between 22 and 35 weeks’ gestation, was used. Motion and labour contraction-free intervals in uEMG were identified as 5-min weak-sense stationarity intervals in 268 (34 PTB) recordings. Sample entropy (SampEn), percentage recurrence (PR), percentage determinism (PD), entropy (ER), and maximum length (L MAX) of recurrence were calculated and analysed according to the time to delivery and PTB. Random time series were generated by random shuffle (RS) of actual data. Recurrence was present in actual data (p < 0.001) but not RS. In S3, PR (p < 0.005), PD (p < 0.01), ER (p < 0.005), and L MAX (p < 0.05) were higher, and SampEn lower (p < 0.005) in PTB. Recurrence indices increased (all p < 0.001) and SampEn decreased (p < 0.01) with decreasing time to delivery, suggesting increasingly regular and recurring patterns with gestation progression. All indices predicted PTB with AUC ≥0.62 (p < 0.05). Recurring patterns in stationary non-contracting uEMG were associated with time to delivery but were relatively poor predictors of PTB. 相似文献
992.
Congjin Chen Shuai Mi Dongmei Lao Panpan Shi Zhangfa Tong Zhixia Li Huayu Hu 《RSC advances》2019,9(39):22248
Eucalyptus wood-based magnetic activated carbon (MAC) was prepared using single-step carbonization activation magnetization with FeCl3 and utilized for the adsorption of methylene blue (MB). The MAC was prepared using the following conditions: the mass ratio of FeCl3 to eucalyptus sawdust was controlled to 2 : 1, the one-step carbonated activated magnetization temperature and time was 700 °C and 75 min. The prepared MAC was evaluated for textural characteristics such as the adsorption capacity, pore structure, surface chemical functional groups, magnetic properties, microcrystalline structure, and the surface morphology using the test methods described in the National Standard of China, these were N2-adsorption–desorption isotherms, Fourier transform infrared spectroscopy (FTIR), value stream mapping (VSM), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Batch experiments were carried out to evaluate the adsorption behavior of MB on the prepared MAC at different temperatures of 298–328 K and MB initial concentration of 50.0–500.0 mg L−1. The results were as follows: the iodine number, methylene blue adsorption and phenol adsorption of the prepared MAC were 473.14, 228.22 and 70.90 mg g−1, respectively; MAC exhibited a microporous and mesoporous structure with a mesoporosity of 36%, the BET specific surface area, average pore diameter and pore volume were 645.23 m2 g−1, 2.71 nm and 0.44 cm3 g−1, respectively, and for the magnetic parameters the following results were found, a Hc of 108.51 Oe, Ms of 30.37 emu g−1 and Mr of 2.46 emu g−1; there were OH, C–O, C O, C C, COO, C–N, and Fe–O groups on the MAC surface, and Fe3O4 existed in the pores and surfaces of the MAC. The MB adsorption on the MAC followed the Langmuir isotherm and Dubinin–Radushkevich isotherm model, the adsorption process was a spontaneous, endothermic chemisorption progress, followed by the pseudo-second-order model, and the adsorption process was influenced by multiple diffusion steps, the pore diffusion process was the rate-controlling step, however, the adsorption process was also affected by the film diffusion and surface adsorption. The results reveal that MAC efficiently adsorbs MB and can be easily separated and recovered by an external magnetic field. The as-prepared MAC could be used as a potential adsorbent for organic pollutant wastewater treatment.Eucalyptus wood-based magnetic activated carbon (MAC) was prepared by single-step carbonization activation magnetization with FeCl3 and utilized for the adsorption of methylene blue (MB). 相似文献
993.
Yu Deng Tong-Ling Shan Wu Tong Xu-Chen Zheng Yi-Yei Guo Hao Zheng San-Jie Cao Xin-Tian Wen Guang-Zhi Tong 《Archives of virology》2014,159(9):2513-2517
The SD0803 strain of the bovine viral diarrhea virus (BVDV) was isolated from a piglet in China in 2008 and has been classified as a novel subgenotype of BVDV-1. To describe the molecular features of this novel subgenotype, we sequenced and characterized the complete genome of the SD0803 virus. The genome is 12,271 bp in length and contains 5′ and 3′ untranslated regions (UTRs) that flank an open reading frame (ORF) encoding a 3,898-amino-acid polypeptide. The full-length genome of the SD0803 strain shares 78.8 % to 83.3 % identity with those of other BVDV-1 strains, 70.0 % to 70.7 % identity with those of BVDV-2 strains, and less than 67.6 % identity with those of other pestiviruses. The highest level of shared identity was 83.3 % between the complete SD0803 genome and that of the ZM-95 strain of BVDV-1. Phylogenetic analysis of the 5′ UTR and the coding sequence for the N-terminal protease fragment of the SD0803 polyprotein indicated that the SD0803 virus is a member of the novel subgenotype BVDV-1q, isolates of which have been identified recently in dairy cattle and camels in China. 相似文献
994.
Efficacy of a high-growth reassortant H1N1 influenza virus vaccine against the classical swine H1N1 subtype influenza virus in mice and pigs 总被引:1,自引:0,他引:1
Feng Wen Hai Yu Fu-ru Yang Meng Huang Sheng Yang Yan-Jun Zhou Ze-Jun Li Guang-Zhi Tong 《Archives of virology》2014,159(11):2957-2967
Swine influenza (SI) is an acute, highly contagious respiratory disease caused by swine influenza A viruses (SwIVs), and it poses a potential global threat to human health. Classical H1N1 (cH1N1) SwIVs are still circulating and remain the predominant subtype in the swine population in China. In this study, a high-growth reassortant virus (GD/PR8) harboring the hemagglutinin (HA) and neuraminidase (NA) genes from a novel cH1N1 isolate in China, A/Swine/Guangdong/1/2011 (GD/11) and six internal genes from the high-growth A/Puerto Rico/8/34(PR8) virus was generated by plasmid-based reverse genetics and tested as a candidate seed virus for the preparation of an inactivated vaccine. The protective efficacy of this vaccine was evaluated in mice and pigs challenged with GD/11 virus. Prime and boost inoculation of GD/PR8 vaccine yielded high-titer serum hemagglutination inhibiting (HI) antibodies and IgG antibodies for GD/11 in both mice and pigs. Complete protection of mice and pigs against cH1N1 SIV challenge was observed, with significantly fewer lung lesions and reduced viral shedding in vaccine-inoculated animals compared with unvaccinated control animals. Our data demonstrated that the GD/PR8 may serve as the seed virus for a promising SwIVs vaccine to protect the swine population. 相似文献
995.
996.
Liping Sun Yanjie Hu Aime Niyonsaba Qiaoxia Tong Li Lu Huiyu Li Shenghua Jie 《Clinical and experimental medicine》2014,14(4):389-395
Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by SFTS virus (SFTSV) with a high fatality rate. But the immunofunction was still unclear. The objective of our study was to assess the immunofunction in SFTS patients. Immunofunction test with flow cytometry which contains CD3+, CD4+ and CD8+ T lymphocytes, B cells and NK cells would be used for detecting serum samples collected from 34 SFTS cases and 20 healthy donors. We found that CD3+ and CD4+ T lymphocytes were significantly diminished in SFTS compared to normal control. In contrast, the percentage of NK cells was elevated. Further analysis revealed that the number of CD3+ and CD4+ T lymphocytes showed that there was a more robust pattern of depression in acute phase and severe SFTS infection compared to the patients in recovery phase and mild SFTS infection. But NK cells were significantly increased in acute phase and severe SFTS. They reverted to the near normal levels in convalescent phase. Additionally, the levels of CD3+ and CD4+ T lymphocytes progressively decreased in death group when compared with the survival group, but the level of B cells was higher. The damages of immune system were obvious, and the immune dysfunction might be partly responsible for disease progression of patients with SFTSV infection. 相似文献
997.
目的:探讨韧带样型纤维瘤病(desmoid-type fibromatosis,DTF)的临床病理特征,提高对DTF的认识和诊断水平。方法:分析14例DTF的临床特征,HE及免疫组化观察其病理学特征。结果:14例DTF均为女性,年龄22~81岁,中位数31.5岁,12例发生于腹部,右侧胸壁2例。光镜下以纤细的梭形细胞与胶原纤维交错排列为特征,细胞无异型性,核分裂像罕见;免疫组化Vimentin和β-catenin阳性,部分表达SMA,不表达S-100、CD34、CD117、Dog-1。手术切除随访4~113个月,1例复发。结论:DTF好发于年轻女性,需要与多种良、恶性梭形细胞肿瘤鉴别,细胞核表达β-catenin对DTF诊断和鉴别诊断有重要价值,手术切除是主要治疗手段,切缘残瘤有较高的复发风险。 相似文献
998.
999.
目的 总结分析三批不同年龄段成批烧创伤患者的临床特点,为成批烧创伤的临床救治、监护及康复治疗提供经验.方法 对解放军第一八一医院2009年至2013年救治的三批26例不同年龄段成批烧创伤临床资料进行回顾性分析.结果 26例患者中学龄期儿童组2例患者和老年组1例特重度烧伤合并吸入性损伤患者均死于多脏器功能衰竭,其余23例患者治愈出院.结论 区域烧创伤救治网的建立、政府层面的行政协调、早期综合救治及监护方案的实施与系统康复训练的有效结合是成批烧创伤救治的关键,能提高救治成功率. 相似文献
1000.
Matrix stiffness has been shown to play an important role in modulating various cell fate processes such as differentiation and cell cycle. Given that the stiffness can be easily tuned by varying the crosslinking density, poly(ethylene glycol) (PEG) hydrogels have been widely used as an artificial cell niche. However, little is known about how changes in the hydrogel crosslinking density may affect the accumulation of exogenous growth factors within 3-D hydrogel scaffolds formed by different crosslinking mechanisms. To address such shortcomings, we measured protein diffusivity and accumulation within PEG hydrogels with varying PEG molecular weight, concentration and crosslinking mechanism. We found that protein accumulation increased substantially above a critical mesh size, which was distinct from the protein diffusivity trend, highlighting the importance of using protein accumulation as a parameter to better predict the cell fates in addition to protein diffusivity, a parameter commonly reported by researchers studying protein diffusion in hydrogels. Furthermore, we found that chain-growth-polymerized gels allowed more protein accumulation than step-growth-polymerized gels, which may be the result of network heterogeneity. The strategy used here can help quantify the effects of varying the hydrogel crosslinking density and crosslinking mechanism on protein diffusion in different types of hydrogel. Such tools could be broadly useful for interpreting cellular responses in hydrogels of varying stiffness for various tissue engineering applications. 相似文献