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111.
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has lasted for two years and caused millions of infections and deaths in humans. Although the origin of SARS-CoV-2 infection in humans remains unknown, infection in animals has been frequently reported in varieties of animals all over the world. Both experimental and natural infections of SARS-CoV-2 in different animal species provide useful information on viral host range and pathogenicity. As the pandemic continues to evolve, SARS-CoV-2 infection in animals will be expanding. In this review, we summarized SARS-CoV-2 testing and infection in animals as well as SARS-CoV-2 strains and transmission in animals. Current data showed that at least 18 different animal species tested positive for SARS-CoV-2. These 18 animal species belong to pet, captive, farmed, and wild animals. Fifteen of the eighteen animal species were known to be positive for the Delta variant and ten animal species were infected with two different types of variants. Human-to-animal, animal-to-animal, and animal-to-human transmission events were suggested in different outbreaks involved in animal infection with SARS-CoV-2. Continued testing, immunization, and surveillance are warranted.  相似文献   
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113.
汪年松  廖履坦  竺艳娟 《上海医学》1999,22(10):600-602
评价血液透析病人HCV阳转率和危险因素。方法随访1995年6月-1996年12月在本院透析的199例血透病人,均未隔离抗-HCV阳性病人。采用敏感的ELISA2每隔3个月在同一实验室检测。结果1995年6月的抗-HCV阳性率为58.7%,每隔半年的阳性率分别为53.7%,54.8%和50.0%。  相似文献   
114.
Tin-bronze alloys with a tin content of at least 10 wt% have excellent mechanical properties, wear resistance, and corrosion resistance. Among these alloys, Cu-10Sn was investigated in this study for production with the laser powder bed fusion process with a 500W Yb:YAG laser. In particular, a design of experiment (DoE) was developed in order to identify the optimal process parameters to obtain full density, low surface roughness, and high dimensional accuracy. Samples were characterized with Archimedes’ method and optical microscopy to determine their final density. It was shown that the first method is fast but not as reliable as the second one. A first mechanical characterization was performed through microhardness tests. Finally, a set of process parameters was identified to produce fully dense samples with low surface roughness and high accuracy. The results showed that the volumetric energy density could represent an approach that is too simplified, therefore limiting the direct correlation with the physical aspects of the process.  相似文献   
115.
This paper introduces an innovative method for making cement-based composites from corn straw plants, and investigates the strength, thermal conductivity, and hydration characteristics of the composites. Corn straw is a natural, renewable, and breathable thermal insulation composite that contains cellular sealed pores. Corn straw contains a large amount of soluble cellulosic sugar, which hinders the hydration reaction of Portland cement and affects the use of corn straw as a building material. In this study, a 3 wt.% siliceous solution was used for surface treatment of corn straw particles to prevent cellulosic sugar from affecting the hydration performance of Portland cement. The composition of added cement-based composite materials with treated corn straw at the dosage of 11–20 wt.% was investigated. The test results showed that the corn straw cement-based composite (CSCC) had an optimal thermal conductivity of 0.102–0.112 (W/(m·K)) and a minimum compressive strength of above 1 MPa. The hydration performance of four typical CSCCs was examined using XRD, SEM, and EDS. The experimental results of this study may help to increase the comprehensive utilization of corn straw. The manufacturing method of the composite materials is simple, effective, and convenient for popularization and application, and it provides a new important technical measure to solve the problem of high energy consumption in rural houses.  相似文献   
116.
冯文  任涛 《中国医院》2014,(7):22-24
为了解某市医院的能源消耗状况,于2012年对该市21家市属医院的各类能源消耗情况进行调查。结果显示,2009年—2011年,除柴油外,医院各种能源的使用量均持续上升,增幅最大的是电力,年增长率8.47%;包括柴油在内的各种能源支出持续增加,年增长率10.74%,增幅最大的是市政热力支出;综合医院的能耗数值及其增长幅度均高于专科医院;医院单位资源的能耗持续增加,单位服务产出的能耗量下降,但单位资源和单位服务量的支出均增加。  相似文献   
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118.
Pain is an unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage. The processing of pain involves complicated modulation at the levels of the periphery, spinal cord, and brain. The pathogenesis of chronic pain is still not fully understood, which makes the clinical treatment challenging. Optogenetics, which combines optical and genetic technologies, can precisely intervene in the activity of specific groups of neurons and elements of the related circuits. Taking advantage of optogenetics, researchers have achieved a body of new findings that shed light on the cellular and circuit mechanisms of pain transmission, pain modulation, and chronic pain both in the periphery and the central nervous system. In this review, we summarize recent findings in pain research using optogenetic approaches and discuss their significance in understanding the pathogenesis of chronic pain.  相似文献   
119.
在12次猪的心脏移植实验中,供心的保护分两组,Ⅰ组供心用冷晶体停搏液灌注,Ⅱ组用温血灌注,在供心取出前及主动脉开放15min后对心肌代谢及酶学的有关指标进行监测。Ⅰ组心肌氧耗率明显低于正常,而Ⅱ组与正常无明显差异。心肌氧耗率下降程度Ⅰ组明显高于Ⅱ组。心肌糖耗率及冠状动静脉pH、磷酸肌酸激酶同功酶差值两组均与正常无明显差异。本实验结果提示间断温血停搏对心肌的保护作用与冷晶体停搏相似,但对于心肌代谢功能的恢复则优于后者。  相似文献   
120.
靛玉红肠吸收转运机制的研究   总被引:11,自引:2,他引:9  
目的:探讨靛玉红肠吸收转运机制。方法:采用缚管翻转肠囊模型,以维拉帕米为P-糖蛋白抑制剂,丙磺舒为多药耐药相关蛋白(MRP)抑制剂,2,4-二硝基苯酚(DNP)为能量抑制剂,考察加入抑制剂前后药物在空肠和回肠部位的转运量的变化。结果:靛玉红在空肠和回肠部位的转运量无显著性差异(P>0.05);加入抑制剂前后在空肠和回肠部位的转运量亦无显著性差异(P>0.05);通过吸收动力学的研究,发现靛玉红的吸收符合一级吸收模型,Ka为0.015 min-1,且单位时间吸收药量与浓度成正比,符合Fick′s扩散原理。结论:靛玉红的小肠吸收为典型的被动扩散吸收机制。  相似文献   
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