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Timothy H Rainer Peter A Cameron DeVilliers Smit Kim L Ong Alex Ng Wing Hung David Chan Po Nin Anil T Ahuja Louis Chan Yik Si Joseph J Y Sung 《BMJ (Clinical research ed.)》2003,326(7403):1354-1358
Objectives To determine the clinical and radiological features of
severe acute respiratory syndrome (SARS) and to evaluate the accuracy of the
World Health Organization''s guidelines on defining cases of SARS.Design Prospective observational study.Setting A newly set up SARS screening clinic in the emergency
department of a university hospital in Hong Kong''s New Territories.Participants 556 hospital staff, patients, and relatives who
attended the screening clinic and who had had contact with someone with
SARS.Main outcome measure Number of confirmed cases of SARS.Results Of the 556 people, 141 were admitted to hospital, and 97 had
confirmed SARS. Fever, chills, malaise, myalgia, rigor, loss of appetite,
vomiting, diarrhoea, and neck pain but not respiratory tract symptoms were
significantly more common among the 97 patients than among the other patients.
The overall accuracy of the WHO guidelines for identifying suspected SARS was
83% and their negative predictive value was 86% (95% confidence interval 83%
to 89%). They had a sensitivity of 26% (17% to 36%) and a specificity of 96%
(93% to 97%).Conclusions Current WHO guidelines for diagnosing suspected SARS may
not be sufficiently sensitive in assessing patients before admission to
hospital. Daily follow up, evaluation of non-respiratory, systemic symptoms,
and chest radiography would be better screening tools. 相似文献
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Hui‐Min Wang Yan‐Ping Shih Su‐Ming Hu Wen‐Tsung Lo Hui‐Min Lin Shih‐Shiu Ding Hsin‐Chi Liao Po‐Huang Liang 《Biotechnology progress》2009,25(6):1582-1586
To quickly find an optimal expression system for recombinant protein production, a set of vectors with the same restriction sites were constructed for parallel cloning of a target gene and recombinant protein production in prokaryotic and eukaryotic expression systems, simultaneously. These vectors include nucleotide sequences encoding protein tags and protease recognition sites for tag removal, followed by the cloning sites 5′‐EcoRI/3′‐XhoI identical in these vectors for ligating with the sticky‐end PCR product of a target gene. Our vectors allow parallel gene cloning and protein production in multiple expression systems with minimal cloning effort. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 相似文献
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D. Esmenjaud R. Voisin C. Van Ghelder N. Bosselut B. Lafargue M. Di Vito E. Dirlewanger J. L. Poëssel M. Kleinhentz 《Tree Genetics & Genomes》2009,5(2):279-289
Sources of resistance in Prunus spp. exhibit different spectra to the root-knot nematodes (RKN) Meloidogyne incognita, Meloidogyne javanica and Meloidogyne floridensis. In this Prunus genus, two dominant genes, Ma with a complete spectrum from the heterozygous Myrobalan plums P.2175 and P.2980 (section Euprunus; subgenus Prunophora) and RMia with a more restricted spectrum from the peaches Nemared and Shalil (subgenus Amygdalus), have been identified. This study characterizes the resistance spectra of interspecific crosses involving (1) previous Myrobalan
and peach sources, (2) two Alnem almonds (subgenus Amygdalus) resistant to M. javanica, and (3) the apricot A.3923, representing a species considered RKN-resistant (section Armeniaca; Prunophora). For both latter species, genetic data could be obtained through F1 crosses with genetically characterized Myrobalans that
conferred their rooting ability for clonal multiplication of the hybrids and permitted their simultaneous evaluation to the
three RKN. Crosses involving either Ma or RMia or both generated the expected resistance spectra. Nemared confirmed the species-specific resistance to M. incognita conferred by RMia. This rootstock, also previously considered resistant to M. javanica, was susceptible to the M. javanica isolate used, what illustrates an isolate-specific resistance to this species. Alnem accessions were shown homozygous resistant
to M. javanica. In the progeny P.2980 × A.3923, Ma markers allowed to distinguish resistant individuals carrying that gene from resistant individuals lacking it. Distribution
of non-Ma individuals in this cross suggested, in the apricot parent, (1) the absence of a major gene allelic to Ma and (2) the presence of a non RKN specific polygenic resistance. 相似文献
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Po‐Shiuan Hsieh Jong‐Shiaw Jin Chih‐Fan Chiang Pei‐Chi Chan Chih‐Hao Chen Kuang‐Chung Shih 《Obesity (Silver Spring, Md.)》2009,17(6):1150-1157
The aim was to examine the role of cyclooxygenase (COX)‐2‐mediated inflammation in the development of obese linked insulin resistance and fatty liver. The rats were fed separately regular diet (CONT), high‐fat diet (HFD) ad libitum, or energy restrictedly for 12 weeks. Rats fed HFD ad libitum were further divided into three subgroups co‐treated with vehicle (HFa), or a selective COX‐2 inhibitor celecoxib (HFa‐Cel) or mesulid (HFa‐Mes). Euglycemic hyperinsulinemic clamp (EHC) experiment was performed at the end of study. Another set of rats with similar grouping was further divided into those with a 4, 8, or 12‐week intervention period for hepatic sampling. Body weight was increased significantly and similarly in HFa, HFa‐Cel, and HFa‐Mes. Time‐dependent increases in plasma insulin, glucose, 8‐isoprostanes, leptin levels, homeostasis model assessment of insulin resistance (HOMA‐IR) and hepatic triglyceride contents shown in HFa were significantly reversed in HFa‐Cel and HFa‐Mes. During EHC period, the reduction in stimulation of whole body glucose uptake, suppression of hepatic glucose production and metabolic clearance rate of insulin shown in HFa were significantly reversed in HFa‐Cel and HFa‐Mes. The enhanced COX‐2 and tumor necrosis factor‐α (TNF‐α) but attenuated PPAR‐γ and C/EBP‐α mRNA expressions in epididymal fat shown in HFa were significantly reversed in HFa‐Cel and HFa‐Mes. The increases in average cell size of adipocytes and CD68 positive cells shown in HFa were also significantly reversed in HFa‐Cel and HFa‐Mes. Our findings suggest that COX‐2 activation in fat inflammation is important in the development of insulin resistance and fatty liver in high fat induced obese rats. 相似文献
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合胞素(Syncytin)是一类由人俘获的逆转录病毒囊膜蛋白,与胎盘的形态发生中细胞滋养层到合胞滋养层的分化过程十分相关。Syncytin与人免疫缺陷病毒I型(HIV-1)囊膜蛋白(Env)在结构上具有相似的特点,二者可能具有相似的膜融合机制。本文通过PCR对融合核心部位七肽重复区HR1和HR2之间linker中自然存在的一对保守的分子内二硫键进行定点突变,表达纯化该突变蛋白,并进行了相应的结构及稳定性探讨,通过与未突变蛋白的性质比较确证该分子内二硫键在蛋白结构的正确形成及稳定性上起着一定的作用。 相似文献