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101.
102.
Li Mao Wenliang Li Fei Hao Leilei Yang Jizong Li Min Sun Wenwen Zhang Maojun Liu Xuenong Luo Zilong Cheng 《Viruses》2022,14(6)
China is the country with the largest number of domestic small ruminants in the world. Recently, the intensive and large-scale sheep/goat raising industry has developed rapidly, especially in nonpastoral regions. Frequent trading, allocation, and transportation result in the introduction and prevalence of new pathogens. Several new viral pathogens (peste des petits ruminants virus, caprine parainfluenza virus type 3, border disease virus, enzootic nasal tumor virus, caprine herpesvirus 1, enterovirus) have been circulating and identified in China, which has attracted extensive attention from both farmers and researchers. During the last decade, studies examining the etiology, epidemiology, pathogenesis, diagnostic methods, and vaccines for these emerging viruses have been conducted. In this review, we focus on the latest findings and research progress related to these newly identified viral pathogens in China, discuss the current situation and problems, and propose research directions and prevention strategies for different diseases in the future. Our aim is to provide comprehensive and valuable information for the prevention and control of these emerging viruses and highlight the importance of surveillance of emerging or re-emerging viruses. 相似文献
103.
双极电凝镊在扁桃体摘除术中的应用 总被引:2,自引:0,他引:2
目的:通过比较采用双极电凝镊与传统的剥离法实施扁桃体摘除的手术效果,探讨双极电凝镊在扁桃体摘除术中的应用效果。方法:选取行扁桃体手术摘除的患者100例,前瞻性地分为两组,比较手术时间、术中出血量及术后患者并发症、疼痛程度及恢复时间。结果:用双极电凝镊行扁桃体摘除与普通法扁桃体摘除相比,手术时间短,术中出血少,术后并发症发生率低,患者痛苦轻。结论:采用双极电凝镊扁桃体摘除手术效果明显优于普通剥离法扁桃体摘除,两方法术后恢复时间无统计学差别。 相似文献
104.
目的探讨抑制素A在预测孕早期先兆流产孕妇妊娠结局中的价值。方法选择孕6~13周稽留流产孕妇18例及B超检查示活胎的先兆流产孕妇27例(妊娠继续组17例和难免流产组10例),同孕龄正常孕妇40例。采用ELISA法测定各组孕妇血清抑制素A水平。结果正常孕妇血清抑制素A在孕早期随孕龄增加而增加,孕10~11周达高峰,孕12~13周逐渐降低。难免流产组血清抑制素A水平明显低于妊娠继续组(P〈0.01);当抑制素A〈0.3 MoM时可筛查出90%的难免流产,敏感性为90%,特异性为94.1%。结论孕早期血清抑制素A的检测有助于预测先兆流产孕妇不良妊娠结局,当血清抑制素A〈0.3 MoM时对预测难免流产有较高的敏感性和特异性。 相似文献
105.
106.
Haiqin Duan Fei Yang Xinmin Shen Qin Yin Enshuai Wang Xiaonan Zhang Xiaocui Yang Cheng Shen Wenqiang Peng 《Materials》2022,15(11)
Acoustic metamaterials based on Helmholtz resonance have perfect sound absorption characteristics with the subwavelength size, but the absorption bandwidth is narrow, which limits the practical applications for noise control with broadband. On the basis of the Fabry–Perot resonance principle, a novel sound absorber of the acoustic metamaterial by parallel connection of the multiple spiral chambers (abbreviated as MSC-AM) is proposed and investigated in this research. Through the theoretical modeling, finite element simulation, sample preparation and experimental validation, the effectiveness and practicability of the MSC-AM are verified. Actual sound absorption coefficients of the MSC-AM in the frequency range of 360–680 Hz (with the bandwidth Δf1 = 320 Hz) are larger than 0.8, which exhibit the extraordinarily low-frequency sound absorption performance. Moreover, actual sound absorption coefficients are above 0.5 in the 350–1600 Hz range (with a bandwidth Δf2 = 1250 Hz), which achieve broadband sound absorption in the low–middle frequency range. According to various actual demands, the structural parameters can be adjusted flexibly to realize the customization of sound absorption bandwidth, which provides a novel way to design and improve acoustic metamaterials to reduce the noise with various frequency bands and has promising prospects of application in low-frequency sound absorption. 相似文献
107.
108.
109.
Kok Hian Tan Fei Dai Mor Jack Ng Pih Lin Tan Seow Heong Yeo Bernard Chern 《Singapore medical journal》2022,63(6):307
INTRODUCTIONThe stillbirth rate (SBR) is an important public health indicator. We studied the distribution of maternal and fetal characteristics and time trends of the SBR at KK Women’s and Children’s Hospital (KKH), Singapore, from 2004 to 2016 based on various definitions of stillbirth.METHODSData was obtained from the Data Warehouse and Stillbirth Reporting System of KKH from 2004 to 2016. SBRs were calculated based on three definitions (fetal deaths at ≥ 20 weeks, 24 weeks or 28 weeks of gestation per 1,000 total births) and were described with maternal and fetal characteristics, and by year.RESULTSFrom 2004 to 2016, the SBR declined by 44.7%, 25.5% and 18.9% based on Definitions I, II and III, respectively. The SBR at KKH in 2016 was 5.2 (Definition I), 4.1 (Definition II) and 3.0 (Definition III) per 1,000 total births. The SBR was significantly higher in women aged ≥ 35 years, nulliparas and female fetuses. The number of live births at 24–27+6 weeks of gestation was more than four times higher than that of stillbirths (822 vs. 176). There were 104 (12.7%) neonatal deaths during this gestation period, giving a high survival rate of 87.3%.CONCLUSIONThe SBR in KKH is relatively lower than that in other developed countries. There is a need to consider revising our hospital and national definitions of the stillbirth lower boundary from 28 weeks to 24 weeks of gestation. This would allow us to make better comparisons with other developed countries, in line with improvements in healthcare. 相似文献
110.
Lili Huang Junying Zhou Yuanfeng Sun Zhe Li Fei Lei Guangyao Zhou Xiangdong Tang 《Psychiatry research》2013
We assessed associations between polysomnographically determined sleep, especially the amount of slow-wave sleep (SWS), and body mass index (BMI) in patients with insomnia. One hundred and forty-one insomniacs and 55 healthy volunteers completed overnight polysomnographic recordings, and we measured height and body weight. No significant correlations were obtained between total sleep time and BMI among insomniacs. Compared with normal volunteers, insomnia patients exhibited longer sleep latency and shorter total sleep duration. While the two groups had no significant differences in BMI, insomniacs presented with more N1 but less time spend in SWS and rapid eye movement sleep (REMS). Based on their SWS time, we divided insomnia patients into three groups: short (26.99±13.88), intermediate (59.24±8.12), and long (102.21±26.17) SWS groups. The short-SWS group had significantly greater BMI than the long-SWS group. Further analyses with multiple linear regression showed a significant negative correlation between the amount of SWS and BMI scores in insomniacs, whereas no such correlation was found in healthy volunteers after controlling for potential confounds (e.g., age, sex and AHI). Our study suggests that low amounts of SWS may be associated with higher BMI in patients with insomnia. 相似文献