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排序方式: 共有771条查询结果,搜索用时 15 毫秒
151.
Haagmans BL Kuiken T Martina BE Fouchier RA Rimmelzwaan GF van Amerongen G van Riel D de Jong T Itamura S Chan KH Tashiro M Osterhaus AD 《Nature medicine》2004,10(3):290-293
The primary cause of severe acute respiratory syndrome (SARS) is a newly discovered coronavirus. Replication of this SARS coronavirus (SCV) occurs mainly in the lower respiratory tract, and causes diffuse alveolar damage. Lack of understanding of the pathogenesis of SARS has prevented the rational development of a therapy against this disease. Here we show extensive SCV antigen expression in type 1 pneumocytes of experimentally infected cynomolgus macaques (Macaca fascicularis) at 4 d postinfection (d.p.i.), indicating that this cell type is the primary target for SCV infection early in the disease, and explaining the subsequent pulmonary damage. We also show that prophylactic treatment of SCV-infected macaques with the antiviral agent pegylated interferon-alpha (IFN-alpha) significantly reduces viral replication and excretion, viral antigen expression by type 1 pneumocytes and pulmonary damage, compared with untreated macaques. Postexposure treatment with pegylated IFN-alpha yielded intermediate results. We therefore suggest that pegylated IFN-alpha protects type 1 pneumocytes from SCV infection, and should be considered a candidate drug for SARS therapy. 相似文献
152.
153.
Brigitte A. G. L. van Cleef Birgit H. B. van Benthem Anja P. J. Haenen Thijs Bosch Jos Monen Jan A. J. W. Kluytmans 《PloS one》2013,8(8)
Methicillin-resistant Staphylococcus aureus (MRSA) is a worldwide problem in both hospitals and communities all over the world. In 2003, a new MRSA clade emerged with a reservoir in pigs and veal calves: livestock-associated MRSA (LA-MRSA). We wanted to estimate the incidence of bacteraemias due to LA-MRSA using national surveillance data from 2009 in the Netherlands. We found a low incidence of LA-MRSA and MRSA bacteraemia episodes, compared to bacteraemias caused by all S. aureus (0.04, 0.18 and 19.3 episodes of bacteraemia per 100,000 inhabitants per year, respectively). LA-MRSA and MRSA were uncommon compared to numbers from other countries as well. MRSA in general and LA-MRSA in specific does not appear to be a public health problem in the Netherlands now. The low incidence of LA-MRSA bacteraemia episodes may best be explained by differences in the populations affected by LA-MRSA versus other MRSA. However, reduced virulence of the strain involved, and the effectiveness of the search and destroy policy might play a role as well. 相似文献
154.
Rogier Bodewes Rebriarina Hapsari Ana Rubio García Guillermo J. Sánchez Contreras Marco W. G. van de Bildt Miranda de Graaf Thijs Kuiken Albert D. M. E. Osterhaus 《PloS one》2014,9(11)
A novel parvovirus was discovered recently in the brain of a harbor seal (Phoca vitulina) with chronic meningo-encephalitis. Phylogenetic analysis of this virus indicated that it belongs to the genus Erythroparvovirus, to which also human parvovirus B19 belongs. In the present study, the prevalence, genetic diversity and clinical relevance of seal parvovirus (SePV) infections was evaluated in both harbor and grey seals (Halichoerus grypus) that lived in Northwestern European coastal waters from 1988 to 2014. To this end, serum and tissue samples collected from seals were tested for the presence of seal parvovirus DNA by real-time PCR and the sequences of the partial NS gene and the complete VP2 gene of positive samples were determined. Seal parvovirus DNA was detected in nine (8%) of the spleen tissues tested and in one (0.5%) of the serum samples tested, including samples collected from seals that died in 1988. Sequence analysis of the partial NS and complete VP2 genes of nine SePV revealed multiple sites with nucleotide substitutions but only one amino acid change in the VP2 gene. Estimated nucleotide substitution rates per year were 2.00×10−4 for the partial NS gene and 1.15×10−4 for the complete VP2 gene. Most samples containing SePV DNA were co-infected with phocine herpesvirus 1 or PDV, so no conclusions could be drawn about the clinical impact of SePV infection alone. The present study is one of the few in which the mutation rates of parvoviruses were evaluated over a period of more than 20 years, especially in a wildlife population, providing additional insights into the genetic diversity of parvoviruses. 相似文献
155.
Cullen S. Hendrix Kristian Skrede Gleditsch 《Biological reviews of the Cambridge Philosophical Society》2012,87(1):163-167
Letendre, Fincher & Thornhill (2010) argue that pathogen intensity provides the ultimate explanation for why some countries are more prone to civil war than others. They argue that the economic and political factors highlighted in previous research on civil war are largely caused by underlying differences in pathogen intensity, and contend that disease proneness increases the risk of civil war through its effects on resource competition and xenophobia. They present empirical evidence that they interpret as consistent with their argument: a statistically significant correlation between pathogen intensity and civil war onset. In this comment, we raise concerns over their interpretation of the empirical evidence and their proposed causal mechanisms. We find that the data provide stronger evidence for the reverse causal relationship, namely that civil war causes disease to become more prevalent. This finding is consistent with the literatures on the public health effects of civil war as well as research on state capacity and public health. 相似文献
156.
Petra Klepac Laura W. Pomeroy Ottar N. Bj?rnstad Thijs Kuiken Albert D.M.E. Osterhaus Jolianne M. Rijks 《Proceedings. Biological sciences / The Royal Society》2009,276(1666):2469-2476
Heterogeneities in transmission among hosts can be very important in shaping infectious disease dynamics. In mammals with strong social organization, such heterogeneities are often structured by functional stage: juveniles, subadults and adults. We investigate the importance of such stage-related heterogeneities in shaping the 2002 phocine distemper virus (PDV) outbreak in the Dutch Wadden Sea, when more than 40 per cent of the harbour seals were killed. We do this by comparing the statistical fit of a hierarchy of models with varying transmission complexity: homogeneous versus heterogeneous mixing and density- versus frequency-dependent transmission. We use the stranding data as a proxy for incidence and use Poisson likelihoods to estimate the ‘who acquires infection from whom’ (WAIFW) matrix. Statistically, the model with strong heterogeneous mixing and density-dependent transmission was found to best describe the transmission dynamics. However, patterns of incidence support a model of frequency-dependent transmission among adults and juveniles. Based on the maximum-likelihood WAIFW matrix estimates, we use the next-generation formalism to calculate an R0 between 2 and 2.5 for the Dutch 2002 PDV epidemic. 相似文献
157.
Jo De Vrieze Thijs De Mulder Silvio Matassa Jizhong Zhou Largus T. Angenent Nico Boon Willy Verstraete 《Microbial biotechnology》2020,13(4):829-843
Pure (single) cultures of microorganisms and mixed microbial communities (microbiomes) have been important for centuries in providing renewable energy, clean water and food products to human society and will continue to play a crucial role to pursue the Sustainable Development Goals. To use microorganisms effectively, microbial engineered processes require adequate control. Microbial communities are shaped by manageable deterministic processes, but also by stochastic processes, which can promote unforeseeable variations and adaptations. Here, we highlight the impact of stochasticity in single culture and microbiome engineering. First, we discuss the concepts and mechanisms of stochasticity in relation to microbial ecology of single cultures and microbiomes. Second, we discuss the consequences of stochasticity in relation to process performance and human health, which are reflected in key disadvantages and important opportunities. Third, we propose a suitable decision tool to deal with stochasticity in which monitoring of stochasticity and setting the boundaries of stochasticity by regulators are central aspects. Stochasticity may give rise to some risks, such as the presence of pathogens in microbiomes. We argue here that by taking the necessary precautions and through clever monitoring and interpretation, these risks can be mitigated. 相似文献
158.
Functional aspects of peritoneal macrophages in endometriosis of women 总被引:11,自引:0,他引:11
G A Dunselman M G Hendrix P X Bouckaert J L Evers 《Journal of reproduction and fertility》1988,82(2):707-710
Peritoneal fluid was collected in the periovulatory phase of the cycle from 25 women undergoing laparoscopy. Endometriosis was diagnosed in 13 patients (AFS score 1, N = 9; AFS score 2, N = 4) and 12 patients without endometriosis served as controls. In endometriosis patients the total peritoneal fluid cell number and cell concentration was significantly higher than in controls, indicating peritoneal irritation by endometrial implants. Peritoneal fluid macrophages in patients with endometriosis showed significantly increased erythrophagocytosis and lower chemiluminescence than in controls, suggesting an advanced differentiation of the macrophages in endometriosis patients. The macrophages in this stage of differentiation may interfere with gametes and embryos and thus contribute to endometriosis-associated subfertility. 相似文献
159.
Suboptimal nitrogen nutrition, leaf aging, and prior exposure to water stress all increased stomatal closure in excised cotton (Gossypium hirsutum L.) leaves supplied abscisic acid (ABA) through the transpiration stream. The effects of water stress and N stress were partially reversed by simultaneous application of kinetin (N6-furfurylaminopurine) with the ABA, but the effect of leaf aging was not. These enhanced responses to ABA could have resulted either from altered rates of ABA release from symplast to apoplast, or from some post-release effect involving ABA transport to, or detection by, the guard cells. Excised leaves were preloaded with [14C]ABA and subjected to overpressures in a pressure chamber to isolate apoplastic solutes in the exudate. Small quantities of 14C were released into the exudate, with the amount increasing greatly with increasing pressure. Over the range of pressures from 1 to 2.5 MPa, ABA in the exudate contained about 70% of the total 14C, and a compound co-chromatographing with phaseic acid contained over half of the remainder. At a low balancing pressure (1 MPa), release of 14C into the exudate was increased by N stress, prior water stress, and leaf aging. Kinetin did not affect 14C release in leaves of any age, N status, or water status. Distribution of ABA between pools can account in part for the effects of water stress, N stress, and leaf age on stomatal behavior, but in the cases of water stress and N stress there are additional kinetinreversible effects, presumably at the guard cells.Abbreviations and symbols ABA
abscisic acid
- PA
phaseic acid
-
w
water potential 相似文献
160.
Anne K. J. Giesbers Erik den Boer David N. J. Braspenning Thijs P. H. Bouten Johan W. Specken Martijn P. W. van Kaauwen Richard G. F. Visser Rients E. Niks Marieke J. W. Jeuken 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2018,131(8):1761-1776