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1.
《Vaccine》2020,38(39):6141-6152
Influenza vaccination is considered the most valuable means to prevent and control seasonal influenza infections, which causes various clinical symptoms, ranging from mild cough and fever to even death. Among various influenza vaccine types, the inactivated subunit type is known to provide improved safety with reduced reactogenicity. However, there are some drawbacks associated with inactivated subunit type vaccines, with the main ones being its low immunogenicity and the induction of Th2-biased immune responses. In this study, we investigated the role of a single-stranded RNA (ssRNA) derived from the intergenic region in the internal ribosome entry site of the Cricket paralysis virus as an adjuvant rather than the universal vaccine for a seasonal inactivated subunit influenza vaccine. The ssRNA adjuvant stimulated not only well-balanced cellular (indicated by IgG2a, IFN-γ, IL-2, and TNF-α) and humoral (indicated by IgG1 and IL-4) immune responses but also a mucosal immune response (indicated by IgA), a key protector against respiratory virus infections. It also increases the HI titer, the surrogate marker of influenza vaccine efficacy. Furthermore, ssRNA adjuvant confers cross-protective immune responses against heterologous influenza virus infection while promoting enhanced viral clearance. Moreover, ssRNA adjuvant increases the number of memory CD4+ and CD8+ T cells, which can be expected to induce long-term immune responses. Therefore, this ssRNA-adjuvanted seasonal inactivated subunit influenza vaccine might be the best influenza vaccine generating robust humoral and cellular immune responses and conferring cross-protective and long-term immunity. 相似文献
2.
采用快速粘度分析仪(RVA)研究了食盐对18种普通玉米杂交种淀粉糊化性质的影响。结果表明:食盐显著降低了所有普通玉米杂交种淀粉的峰值、破损值和回生值;提高了谷值、终粘度、出峰时间和成糊温度。但对不同的普通玉米杂交种淀粉的糊化性质的影响程度有显著差别。随着食盐溶液质量分数的增加,普通玉米杂交种淀粉的谷值、终粘度、出峰时间和成糊温度也逐渐增加,破损值和回生值则显著降低,峰值受食盐溶液质量分数的影响很小。 相似文献
3.
Despite the use of gold complexes in modern medicine for over 100 years and the use of gold complexes in the management of
rheumatoid disease for more than 60 years, the definitive mechanisms of action for efficacy and for toxicity have not been
established.
Gold is a group 1b metal in the periodic table with several oxidation states but it is only Au(I) which is active in the biological
milieu. Gold sodium thiomalate is not only a polymeric structure, but also has the chiral ligand, thiomalic acid. Gold sodium
thiomalate thus can exist in several different physical states which may have different biological activity. In addition the
pharmacokinetic profile of gold complexes has been of little value in the understanding of either the mechanism of action,
efficacy or toxicity for both the injectable and the oral gold complexes. Many authors have misinterpreted research data on
the activities of gold complexes because they compared gold complexes of different structures, and gold complexes which exist
at different pH.
Experimental work in our laboratory has identified that gold sodium thiomalate is a mixture and can exist as either a yellow
or a colourless solution. These have some similar but several different biological activities.
Many factors contribute to the lack of understanding of the action of gold complexes. Some of these factors are related to
the wide variation in physical structure and biological activities exhibited by these compounds. 相似文献
4.
E. Perucca R. Grimaldi G. Ruberto C. Gelmi F. Trimarchi A. Crema 《European journal of clinical pharmacology》1986,29(6):729-730
Summary The kinetics of phenobarbital (PB) was compared after oral administration of equivalent doses of the drug as the acid or the propylhexedrine salt (barbexaclone) to 7 normal volunteers. The absorption and elimination parameters were very similar. It was concluded that propylhexedrine did not affect the serum kinetics of PB given as barbexaclone. 相似文献
5.
WEIGUANG ZENG PIERRE-OLIVIER REGAMEY KEITH ROSE YUZHOU WANG ERNST BAYER 《Chemical biology & drug design》1997,49(3):273-279
The use of N, O-bisFmoc-N-(2-hydroxy-4-methoxybenzyl) amino acid derivatives in the synthesis of peptides with difficult sequences has already been described. With these amino acid derivatives the reversible protecting group 2-hydroxy-4-methoxybenzyl (Hmb) for the backbone amide bonds of peptide chains is introduced, and thus the aggregation due to hydrogen-bond interchain association is inhibited. This paper describes the synthesis and use of Fmoc-N-(2-hydroxy-4-methoxybenzyl)amino acid derivatives as an alternative means of introducing Hmb backbone protection. These new monoFmoc derivatives were obtained in higher yield than the bisFmoc derivatives. Coupling yields to the amino peptide resin were the same as those obtained with bisFmoc derivatives, under the TBTU/HOBt/DIEA conditions. We also compared different syntheses of a difficult peptide with the Fmoc approach [triple coupling, capping, use of chaotropic agents, backbone protection using monoFmoc (Hmb)Ala] and with optimized Boc chemistry. Both the backbone protection and optimized Boc chemistry approaches gave the desired product in excellent yield and purity. © Munksgaard 1997. 相似文献
6.
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8.
J. C. Mathers 《Journal of human nutrition and dietetics》1988,1(3):155-161
Eleven healthy free-living adults (six women, five men) weighed and recorded all food and drink consumed and collected all urine for two non-consecutive 7-day periods whilst eating their usual diet (Period 1) and attempting to reduce salt intake (Period 2). Bread (including pitta bread) provided on average a quarter of total Na intake of subjects in Period 1 so that wholemeal bread made without added salt was made available in Period 2. All subjects achieved substantial reductions (mean 65%) in Na intake in Period 2 with no change in K intake so that the Na:K molar ratio fell from 1.3 to 0.5. Urinary Na output closely followed intakes and there was a large increase (mean 11.2 μg/d) in aldosterone excretion with a non-significant increase in K output. Simple linear relationships which allow prediction of Na and K intake from the more easily measured urinary output were derived. 相似文献
9.
本文对化学试剂厂从事钼盐产品专业厂的105名职工详细询问了病史,并进行了眼科全面检查。受检者分为接触组83人和对照组22人。接触毒物主要为钼盐类。检查结果表明2组受检者在眼部症状、眼病史、外眼病发生率、角膜知觉、调节近点、辐辏近点诸方面有显著性差异。角膜染色2组间无显著性,但2组与正常人群比较均有显著性,说明钼盐类化学物质对作业工人眼部有一定的影响。本文并提出相应的防护措施。 相似文献
10.
Kazushi Tsuda Keizo Kimura Hiroki Shima Ichiro Nishio Yoshiaki Masuyama 《Clinical and experimental pharmacology & physiology》1992,19(7):531-535
The present study was designed to investigate the presynaptic alpha 2-adrenoceptor function to inhibit norepinephrine (NE) release in blood vessels of reduced renal mass salt hypertensive rats (Na-loaded HT). Isolated perfused mesenteric vasculatures were prepared from Na-loaded HT and normotensive control rats (NT-control), and the NE release and vascular responsiveness were examined. Periarterial nerve stimulation caused a significantly greater release of NE and pressor responses in Na-loaded HT than in NT-control. Yohimbine, a potent alpha 2-adrenoceptor antagonist, demonstrated the facilitatory effects on NE release during nerve stimulation. The effects were significantly attenuated in Na-loaded HT compared with NT-control. These results demonstrate that vascular sympathetic nervous activity might be enhanced in Na-loaded HT. Furthermore, the increased NE release from vascular adrenergic neurons in Na-loaded HT could partially depend on impaired presynaptic alpha 2-adrenoceptor-mediated modulation, which might contribute to the pathogenesis and maintenance of this form of salt-dependent hypertension. 相似文献