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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Sina Schwarzkopf Adalbert Krawczyk Dietmar Knop Hannes Klump Andreas Heinold Falko M. Heinemann Laura Thümmler Christian Temme Marianne Breyer Oliver Witzke Ulf Dittmer Veronika Lenz Peter A. Horn Monika Lindemann 《Emerging infectious diseases》2021,27(1):122
We investigated immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among a group of convalescent, potential blood donors in Germany who had PCR-confirmed SARS-CoV-2 infection. Sixty days after onset of symptoms, 13/78 (17%) study participants had borderline or negative results to an ELISA detecting IgG against the S1 protein of SARS-CoV-2. We analyzed participants with PCR-confirmed infection who had strong antibody responses (ratio >3) as positive controls and participants without symptoms of SARS-CoV-2 infection and without household contact with infected patients as negative controls. Using interferon-γ ELISpot, we observed that 78% of PCR-positive volunteers with undetectable antibodies showed T cell immunity against SARS-CoV-2. We observed a similar frequency (80%) of T-cell immunity in convalescent donors with strong antibody responses but did not detect immunity in negative controls. We concluded that, in convalescent patients with undetectable SARS-CoV-2 IgG, immunity may be mediated through T cells. 相似文献
82.
Daniel T.L. Shek Li Zhao Diya Dou Xiaoqin Zhu Chenghan Xiao 《The Journal of adolescent health》2021,68(4):676-682
PurposeThis study examined the prevalence of posttraumatic stress disorder (PTSD) symptoms among adolescents in mainland China under COVID-19. The direct effects of the perceived threat of COVID-19 and positive youth development (PYD) qualities, as well as the moderating effect of PYD qualities on PTSD symptoms, were studied.MethodsFive schools in Chengdu, Sichuan, China, participated in this study. Two waves of data were collected before school lockdown (Wave 1, between December 2019 and January 2020) and after school resumption (Wave 2, between June 2020 and July 2020), respectively. A total of 4,981 adolescents aged above 11 years (Mean age = 13.15, SD = 1.32 at Wave 1, 51.5% girls) completed questionnaires at both waves. Students responded to measures of PYD qualities at both waves and perceived threat and PTSD symptoms at Wave 2.ResultsA total of 517 adolescents (10.4%) could be regarded as having PTSD. Results indicated significant unique main effects of perceived threat (β = .13, p < .001) and Wave 1 PYD qualities (β = ?.16, p < .001) on PTSD symptoms. Besides, results showed a significant moderating effect of PYD qualities in mitigating the negative impact of perceived threat on PTSD symptoms.ConclusionsThis study revealed the protective effect of PYD attributes in reducing the negative influence of traumatic situations such as COVID-19 on adolescent mental health. Results underscore the importance of promoting PYD qualities in adolescents in mainland China via effective PYD programs. 相似文献
83.
Kenneth Siu-Sing Leung Timothy Ting-Leung Ng Alan Ka-Lun Wu Miranda Chong-Yee Yau Hiu-Yin Lao Ming-Pan Choi Kingsley King-Gee Tam Lam-Kwong Lee Barry Kin-Chung Wong Alex Yat Man Ho Kam-Tong Yip Kwok-Cheung Lung Raymond Wai-To Liu Eugene Yuk-Keung Tso Wai-Shing Leung Man-Chun Chan Yuk-Yung Ng Kit-Man Sin Kitty Sau-Chun Fung Sandy Ka-Yee Chau Wing-Kin To Tak-Lun Que David Ho-Keung Shum Shea Ping Yip Wing Cheong Yam Gilman Kit-Hang Siu 《Emerging infectious diseases》2021,27(1):196
Initial cases of coronavirus disease in Hong Kong were imported from mainland China. A dramatic increase in case numbers was seen in February 2020. Most case-patients had no recent travel history, suggesting the presence of transmission chains in the local community. We collected demographic, clinical, and epidemiologic data from 50 patients, who accounted for 53.8% of total reported case-patients as of February 28, 2020. We performed whole-genome sequencing to determine phylogenetic relationship and transmission dynamics of severe acute respiratory syndrome coronavirus 2 infections. By using phylogenetic analysis, we attributed the community outbreak to 2 lineages; 1 harbored a common mutation, Orf3a-G251V, and accounted for 88.0% of the cases in our study. The estimated time to the most recent common ancestor of local coronavirus disease outbreak was December 24, 2019, with an evolutionary rate of 3.04 × 10−3 substitutions/site/year. The reproduction number was 1.84, indicating ongoing community spread. 相似文献
84.
Pyoeng Gyun Choe Chang Kyung Kang Hyeon Jeong Suh Jongtak Jung Kyoung-Ho Song Ji Hwan Bang Eu Suk Kim Hong Bin Kim Sang Won Park Nam Joong Kim Wan Beom Park Myoung-don Oh 《Emerging infectious diseases》2021,27(1):327
We investigated the kinetics of severe acute respiratory syndrome coronavirus 2 neutralizing antibodies in 7 asymptomatic persons and 11 patients with pneumonia. The geometric mean titer of neutralizing antibodies declined from 219.4 at 2 months to 143.7 at 5 months after infection, indicating a waning antibody response. 相似文献
85.
Andrea Calcagno Valeria Ghisetti Teresa Emanuele Mattia Trunfio Silvia Faraoni Lucio Boglione Elisa Burdino Sabrina Audagnotto Filippo Lipani Marco Nigra Antonio DAvolio Stefano Bonora Giovanni Di Perri 《Emerging infectious diseases》2021,27(1):303
We measured severe acute respiratory syndrome coronavirus 2 spike protein subunits S1/S2 antibodies by using capillary electrophoresis and a chemiluminescence immunoassay for 5,444 active healthcare workers in Italy. Seroprevalence was 6.9% and higher among participants having contact with patients. Seroconversion was not observed in 37/213 previously infected participants. 相似文献
86.
Fabian Heinrich Kira Meißner Felicia Langenwalder Klaus Püschel Dominik Nrz Armin Hoffmann Marc Lütgehetmann Martin Aepfelbacher Eric Bibiza-Freiwald Susanne Pfefferle Axel Heinemann 《Emerging infectious diseases》2021,27(1):329
Analyses of infection chains have demonstrated that severe acute respiratory syndrome coronavirus 2 is highly transmissive. However, data on postmortem stability and infectivity are lacking. Our finding of nasopharyngeal viral RNA stability in 79 corpses showed no time-dependent decrease. Maintained infectivity is supported by virus isolation up to 35 hours postmortem. 相似文献
87.
Catherine A. Hogan ChunHong Huang Malaya K. Sahoo Hannah Wang Becky Jiang Mamdouh Sibai Marisa Holubar Roshni Mathew James Zehnder Benjamin A. Pinsky 《Emerging infectious diseases》2021,27(2):632
We developed an assay that detects minus-strand RNA as a surrogate for actively replicating severe acute respiratory syndrome coronavirus 2. We detected minus-strand RNA in 41 persons with coronavirus disease up to 30 days after symptom onset. This assay might inform clinical decision-making about patient infectiousness. 相似文献
88.
89.
90.
Lorenz Ulrich Anna Michelitsch Nico Halwe Kerstin Wernike Donata Hoffmann Martin Beer 《Emerging infectious diseases》2021,27(4):1193
After experimental inoculation, severe acute respiratory syndrome coronavirus 2 infection was confirmed in bank voles by seroconversion within 8 days and detection of viral RNA in nasal tissue for up to 21 days. However, transmission to contact animals was not detected. Thus, bank voles are unlikely to establish effective transmission cycles in nature. 相似文献