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81.
陈天慧 《广东微量元素科学》1995,2(2):32-35
“复感儿”即呼吸道反复感染患儿,为探求复感儿体内微量元素变化及与其病因的关系,随机选择成都地区100例肺脾气虚挟痰型复感儿发样,测定其中8种微量元素含量,结果表明:镁缺乏高达83%,锌缺乏占68%,铁缺乏占53%,硒缺乏占15.2%,钙缺乏占14%,磷缺乏占10.1%,铜缺乏5%,锰缺乏占1.63%,提示:此型复感儿不仅有锌、铁缺乏外,更应重视镁缺乏,也应重视硒、钙、磷缺乏,采用中药羔方治疗,效果最佳。 相似文献
82.
Effective combination therapy usually reduces the plasma viral load of HIV to below the detection limit, but it cannot eradicate the virus. The latently infected cell activation is considered to be the main obstacle to completely eradicating HIV infection. In this paper, we consider an HIV infection model with latently infected cell activation, virus diffusion and spatial heterogeneity under Neumann boundary condition. The basic reproduction ratio is characterized by the principal eigenvalue of the related elliptic eigenvalue problem. Besides, by constructing Lyapunov functionals and using Green’s first identity, the global threshold dynamics of the system are completely established. Numerical simulations are carried out to illustrate the theoretical results, in particular, the influence of virus diffusion rate on the basic reproduction ratio is addressed. 相似文献
83.
Intracranial bacterial infection remains a major cause of morbidity and mortality in neurosurgical cases. Metabolomic profiling of cerebrospinal fluid (CSF) holds great promise to gain insights into the pathogenesis of central neural system (CNS) bacterial infections. In this pilot study, we analyzed the metabolites in CSF of CNS infection patients and controls in a pseudo-targeted manner, aiming at elucidating the metabolic dysregulation in response to postoperative intracranial bacterial infection of pediatric cases. Untargeted analysis uncovered 597 metabolites, and screened out 206 differential metabolites in case of infection. Targeted verification and pathway analysis filtered out the glycolysis, amino acids metabolism and purine metabolism pathways as potential pathological pathways. These perturbed pathways are involved in the infection-induced oxidative stress and immune response. Characterization of the infection-induced metabolic changes can provide robust biomarkers of CNS bacterial infection for clinical diagnosis, novel pathways for pathological investigation, and new targets for treatment. 相似文献
84.
Anna Kurek-Grecka Karolina Walczyska-Dragon Rafael Felitti Stefan Baron Pawe Olczyk 《Molecules (Basel, Switzerland)》2022,27(1)
Conducted studies indicate the relationship between oral health and systemic diseases. Moreover, the latest research indicated that cariogenic bacteria may severely influence the course of SARS-CoV-2 infection and increase risk of COVID-19 complications. This article aims to review various applications of propolis and pay attention to a healthy diet rich in polyphenols, which may allow the reduction of dental plaque accumulation. A literature review has been conducted from June until November 2021. It showed that propolis could be a useful agent in decreasing the accumulation of dental plaque. Moreover, a diet rich in polyphenols prevents cariogenic bacteria and reduces the accumulation of dental plaque. A reduction of a dental plaque may influence the risk of a severe course of COVID-19. Therefore, propolis and a diet rich in polyphenols may play an important role in prophylaxis of systemic diseases. Recently, it has been proven that oral infection may affect cardiovascular system, musculoskeletal system, respiratory system, nervous system, as well as may be a risk factor for diabetes mellitus. These aspects should stimulate clinicians to further research about polyphenols. 相似文献
85.
86.
徐格 《广东微量元素科学》2001,8(5):19-22
HIV感染及AIDS至今依然严重威胁着人类的生命,因而成为医学界研究的热点。本文着重从硒与细胞因子角度揭示硒与HIV和AIDS在发生、发展中的关系,证明其扮演的重要角色,提示了一种研究HIV和AIDS的新方向。 相似文献
87.
Jiawei He Jing Wang Li Cao Xiaogang Zhang Guoqing Li Boyong Xu Baochao Ji Jun Zhao Junjie Huang Jianhua Yang 《Journal of mass spectrometry : JMS》2024,59(6):e5041
Numerous studies have suggested that intra-articular administration of antibiotics following primary revision surgery may be one of the methods for treating prosthetic joint infection (PJI). Vancomycin and meropenem are the two most commonly used antibiotics for local application. Determining the concentrations of vancomycin and meropenem in the serum and synovial fluid of patients with PJI plays a significant role in further optimizing local medication schemes and effectively eradicating biofilm infections. This study aimed to establish a rapid, sensitive, and accurate ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method for determining the concentrations of vancomycin and meropenem in human serum and synovial fluid. Serum samples were processed using acetonitrile precipitation of proteins and dichloromethane extraction, while synovial fluid samples were diluted before analysis. Chromatographic separation was achieved in 6 min on a Waters Acquity UPLC BEH C18 column, with the mobile phase consisting of 0.1% formic acid in water (solvent A) and acetonitrile (solvent B). Quantification was carried out using a Waters XEVO TQD triple quadrupole mass spectrometer with an electrospray ionization (ESI) source in positive ion mode. The multiple reaction monitoring (MRM) mode was employed to detect the following quantifier ion transitions: 717.95–99.97 (norvancomycin), 725.90–100.04 (vancomycin), 384.16–67.99 (meropenem). The method validation conformed to the guidelines of the FDA and the Chinese Pharmacopoeia. The method demonstrated good linearity within the range of 0.5–50 μg/ml for serum and 0.5–100 μg/ml for synovial fluid. Selectivity, intra-day and inter-day precision and accuracy, extraction recovery, matrix effect, and stability validation results all met the required standards. This method has been successfully applied in the pharmacokinetic/pharmacodynamic (PK/PD) studies of patients with PJI. 相似文献
88.
We incorporate basic genetics into an AIDS model. We illustrate that if a homozygote is immune to the disease or is resistant to the effects of the disease, the corresponding allele goes to fixation. On the other hand, if the heterozygote is immune to the disease or is resistant to the effects of the disease, polymorphism usually occurs. 相似文献
89.
Yang Junyuan Zhang Fengqin Wang Xiaoyan 《Annals of Differential Equations》2007,23(4):546-551
Saturating contact rate of individual contacts is crucial in an epidemiology model.A mathematical SIR model with saturation incidence and age of infec- tion is formulated in this paper.In addition,we study the dynamical behavior of this model and define the basic reproductive number R_0.The authors also prove that the diseased-free equilibrium is globally asymptotically stable if R_0<1. The endemic equilibrium is locally asymptotically stable if K_1>αand R_0>1. 相似文献
90.
Sumati Bhatia Malte Hilsch Jose Luis Cuellar‐Camacho Kai Ludwig Chuanxiong Nie Badri Parshad Matthias Wallert Stephan Block Daniel Lauster Christoph Bttcher Andreas Herrmann Rainer Haag 《Angewandte Chemie (International ed. in English)》2020,59(30):12417-12422
Flexible multivalent 3D nanosystems that can deform and adapt onto the virus surface via specific ligand–receptor multivalent interactions can efficiently block virus adhesion onto the cell. We here report on the synthesis of a 250 nm sized flexible sialylated nanogel that adapts onto the influenza A virus (IAV) surface via multivalent binding of its sialic acid (SA) residues with hemagglutinin spike proteins on the virus surface. We could demonstrate that the high flexibility of sialylated nanogel improves IAV inhibition by 400 times as compared to a rigid sialylated nanogel in the hemagglutination inhibition assay. The flexible sialylated nanogel efficiently inhibits the influenza A/X31 (H3N2) infection with IC50 values in low picomolar concentrations and also blocks the virus entry into MDCK‐II cells. 相似文献