您当前的位置: 首页 > 最新研究

最新研究共计 2,617 条信息

      全选  导出

1 Medicalxpress,1月13日,Preliminary research suggests SARS-CoV-2 virus less infectious within five minutes of exposure to air 2022-01-25

In astudy that has not yet been peer-reviewed or accepted for publication,researchers at Bristol University in the U.K.have found evidence that suggests the SARS-CoV-2 virus becomes less infectious within five minutes of exposure to air.The team has published apaper on the pre-print server MedRxiv describing tests designed to simulate the behavior of the virus after it is transmitted into the air by an infected person. Since the pandemic first began,health care officials have been asking people around the world to wear amask.The main purpose of such masks for non-health-care workers is to slow the speed with which the virus is transmitted into the air as aperson exhales,sneezes or coughs.The thinking has been that wearing amask helps to protect those around an infected person.In this new effort,the researchers found evidence that suggests the virus,once transmitted into the air,has only five minutes until it starts losing its ability to infect other people.If the finding proves to be accurate,wearing amask becomes even more important.Preventing the virus from sailing across an open space when it only has five minutes to infect someone would reduce its transmissibility drastically. The researchers chose asimulation method that has not been used by other researchers—instead of using Goldberg drums,they created an apparatus that generates and levitates viruses between electric rings.The virus samples are thus held in astate in which their infectiousness could be measured. The researchers found that its transmissibility began dropping within five minutes of exposure to the air.A closer look showed that this is because it begins to dry out and suffers alack of carbon dioxide.They found that after 20 minutes,the transmissibility of the virus was reduced by 90 percent.They also found that more humid air slowed the loss of transmissibility,and that temperature had no impact. At this time,it is not yet clear how well the method matches with conditions in anatural environment.Also,the new method does not take into account ventilation,room size or the viral load of the infected person.And finally,it is still not known what level of transmissibility the virus must have in order to infect people. 查看详细>>

来源: 点击量:0

2 Medicalxpress,1月13日,Maternal COVID-19 infection increases risks of preterm birth, low birth weight and stillbirth 2022-01-25

People who contracted COVID-19 while pregnant were more likely to have poor birth outcomes including preterm birth,small for gestational age,low birth weight,and stillbirth.The poor outcomes of preterm birth and stillbirth were observed primarily with those infected with SARS-CoV-2 during the first or second trimester,whereas increased rates of small for gestational age were driven largely by third trimester infection. An Institute for Systems Biology-led study examined the electronic health records of more than 18,000 people with SARS-CoV-2 tests during pregnancy.Researchers compared outcomes of unvaccinated people with apositive test during pregnancy—882 in total—to those who tested negative. "We found that SARS-CoV-2 infection indicated increased rates of preterm delivery and stillbirth,largely driven by first and second trimester infections,"said Samantha Piekos,Ph.D.,first author of the study.She added:"The single greatest predictor of gestational age at delivery is gestational age at infection,with earlier age at infection associated with earlier age at delivery." The study results were used by the Centers for Disease Control and Prevention to support the use of booster shots. 查看详细>>

来源: 点击量:0

3 Medicalxpress,1月12日,Researchers use artificial intelligence to guide the search for the next SARS-like virus 2022-01-25

Vaccination offers long-lasting protection from the worst outcomes of COVID-19,according to anew study by the University of North Carolina at Chapel Hill. The emergence of the delta and omicron variants has raised questions about whether breakthrough infections are caused by waning immunity or by the more transmissible variants. Results of the study published in the New England Journal of Medicine suggest that declining immunity is responsible for breakthrough infections,but vaccines maintained protection from hospitalization and severe disease nine months after getting the first shot. "The primary takeaway message from our study is that unvaccinated people should get vaccinated right away,"said lead study author Danyu Lin,Ph.D.,Dennis Gillings Distinguished Professor of Biostatistics at the UNC Gillings School of Global Public Health."The results of our study also underscore the importance of booster shots,especially for older adults." The study,which is acollaboration between the UNC-Chapel Hill and the North Carolina Department of Health and Human Services,examined data on COVID-19 vaccination history and health outcomes for 10.6 million North Carolina residents between December 2020 and September 2021. 查看详细>>

来源: 点击量:0

4 Phys.org,1月11日,Catching the COVID wiggle: Researchers develop new way to visualize how the spike protein shows off its moves 2022-01-25

Coronaviruses are slippery,and that makes it hard to create effective vaccines that provide long-term protection.Now,University of Connectiut(UConn)researchers have developed anew way to model the spike protein of the virus and test its binding to antibodies.That could give scientists afirmer grip on the virus that causes COVID-19. By now,the majority of adult citizens in the US have been vaccinated against COVID,and many have had booster shots as well.Despite this,about 30%of hospitalized COVID patients in Connecticut are fully vaccinated.Although there are several different COVID vaccines in use around the world,none of them provides long-term,durable protection against the virus. The problem is the coronavirus's spike protein.The spikes coat the virus,and are so wiggly and flexible that they slip through the clutches of antibodies like aweasel through awedding ring.Without afirm grasp on the spike,the immune system cannot make good antibodies.And without good neutralizing antibodies,the immune system's memory of the virus is too fuzzy to last. 查看详细>>

来源: 点击量:0

版权所有@2017中国科学院文献情报中心

制作维护:中国科学院文献情报中心信息系统部地址:北京中关村北四环西路33号邮政编号:100190