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11.
冠心病中血糖与血清微量元素间的关系分析 总被引:1,自引:0,他引:1
对75例冠心病患者依血糖水平分两组,进行12种血清微量元素测定,旨在探讨微量元素与冠心病及糖尿病间的相互关系。结果发现锌、铬、锰、硒、钴元素高血糖组较对照组血清水平为低,呈非常显著差异(P<0.0l);铜、镍元素增高,差异显著(P<0.05);而锶、铁、砷、铅、铝元素两组间无显著差异(P>0.1)。表明部分微量元素与冠心病及血糖间存在着密切联系。 相似文献
12.
目的:探讨血清白介素-32(interleukin-32,IL-32)水平与先天性心脏病相关肺动脉高压(pulmonary arterial hypertension,PAH)的存在和严重程度之间的关系。方法:试验组纳入85例CHD患者,根据右心导管术测得的平均肺动脉压(mean pulmonary artery pressure,PAPm)将其分为:无PAH组(PAPm≤20 mmHg)、灰色区间组(20 mmHg相似文献
13.
Van QN Klose JR Lucas DA Prieto DA Luke B Collins J Burt SK Chmurny GN Issaq HJ Conrads TP Veenstra TD Keay SK 《Disease markers》2003,19(4-5):169-183
The advent of systems biology approaches that have stemmed from the sequencing of the human genome has led to the search for new methods to diagnose diseases. While much effort has been focused on the identification of disease-specific biomarkers, recent efforts are underway toward the use of proteomic and metabonomic patterns to indicate disease. We have developed and contrasted the use of both proteomic and metabonomic patterns in urine for the detection of interstitial cystitis (IC). The methodology relies on advanced bioinformatics to scrutinize information contained within mass spectrometry (MS) and high-resolution proton nuclear magnetic resonance (1H-NMR) spectral patterns to distinguish IC-affected from non-affected individuals as well as those suffering from bacterial cystitis (BC). We have applied a novel pattern recognition tool that employs an unsupervised system (self-organizing-type cluster mapping) as a fitness test for a supervised system (a genetic algorithm). With this approach, a training set comprised of mass spectra and 1H-NMR spectra from urine derived from either unaffected individuals or patients with IC is employed so that the most fit combination of relative, normalized intensity features defined at precise m/z or chemical shift values plotted in n-space can reliably distinguish the cohorts used in training. Using this bioinformatic approach, we were able to discriminate spectral patterns associated with IC-affected, BC-affected, and unaffected patients with a success rate of approximately 84%. 相似文献
14.
Effect of carrier selection on immunogenicity of protein conjugate vaccines against Plasmodium falciparum circumsporozoites.
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J U Que S J Cryz Jr R Ballou E Fürer M Gross J Young G F Wasserman L A Loomis J C Sadoff 《Infection and immunity》1988,56(10):2645-2649
Conjugate vaccines against the sporozoite stage of Plasmodium falciparum were synthesized by covalently coupling the recombinant protein R32 [with the one-letter amino acid code of MDP-[(NANP)15NVDP]2LR] to tetanus toxoid, cholera toxin, choleragenoid, and Pseudomonas aeruginosa toxin A. Conjugates were produced by using adipic acid dihydrazide as a spacer molecule and carbodiimide as a coupling agent. The molar ratio of R32 to carrier protein ranged from 2.5:1 to 8.4:1. These conjugates were found to be stable, nontoxic, and nonpyrogenic. When adsorbed onto Al(OH)3, all conjugates were capable of inducing anti-R32 antibody. Conjugates made with either cholera toxin or Pseudomonas aeruginosa toxin A were significantly more immunogenic than those constructed with tetanus toxoid or choleragenoid. However, the magnitude of the immune response to the R32 moiety was not governed by the antibody response to the carrier protein. 相似文献
15.
Heterologously expressed Staphylococcus aureus fibronectin-binding proteins are sufficient for invasion of host cells 总被引:8,自引:0,他引:8
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Sinha B Francois P Que YA Hussain M Heilmann C Moreillon P Lew D Krause KH Peters G Herrmann M 《Infection and immunity》2000,68(12):6871-6878
Staphylococcus aureus invasion of mammalian cells, including epithelial, endothelial, and fibroblastic cells, critically depends on fibronectin bridging between S. aureus fibronectin-binding proteins (FnBPs) and the host fibronectin receptor integrin alpha(5)beta(1) (B. Sinha et al., Cell. Microbiol. 1:101-117, 1999). However, it is unknown whether this mechanism is sufficient for S. aureus invasion. To address this question, various S. aureus adhesins (FnBPA, FnBPB, and clumping factor [ClfA]) were expressed in Staphylococcus carnosus and Lactococcus lactis subsp. cremoris. Both noninvasive gram-positive microorganisms are genetically distinct from S. aureus, lack any known S. aureus surface protein, and do not bind fibronectin. Transformants of S. carnosus and L. lactis harboring plasmids coding for various S. aureus surface proteins (FnBPA, FnBPB, and ClfA) functionally expressed adhesins (as determined by bacterial clumping in plasma, specific latex agglutination, Western ligand blotting, and binding to immobilized and soluble fibronectin). FnBPA or FnBPB but not of ClfA conferred invasiveness to S. carnosus and L. lactis. Invasion of 293 cells by transformants was comparable to that of strongly invasive S. aureus strain Cowan 1. Binding of soluble and immobilized fibronectin paralleled invasiveness, demonstrating that the amount of accessible surface FnBPs is rate limiting. Thus, S. aureus FnBPs confer invasiveness to noninvasive, apathogenic gram-positive cocci. Furthermore, FnBP-coated polystyrene beads were internalized by 293 cells, demonstrating that FnBPs are sufficient for invasion of host cells without the need for (S. aureus-specific) coreceptors. 相似文献
16.
Ho PL Tsang DN Que TL Ho M Yuen KY 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2000,108(3):237-240
Three tests, the disk diffusion test, the double-disc synergy test and the inhibitor-potentiated disc diffusion test, were compared for their abilities to detect production of extended-spectrum beta-lactamases (ESBL) in 702 Escherichia coli and 472 Klebsiella spp. strains from four hospitals. Eleven percent E. coli and 13% Klebsiella spp. were found to produce ESBL. As an indicator of ESBL activity, the sensitivities of the five extended-spectrum beta-lactams were as follows: cefotaxime (100%), cefpodoxime (99.3%), ceftriaxone (98.6%), aztreonam (93%) and ceftazidime (57.7%) when interpreted using the National Committee for Clinical Laboratory Standards criteria. Their positive predictive values ranged from 67.8-83.8%. Both the inhibitor-potentiated disc diffusion test and the double-disc synergy test (at three inter-disc widths of 20, 25 and 30 mm) were capable of identifying all the ESBL-producers. However, at a single inter-disc width of 30 mm, the double-disc synergy test has limited sensitivity (83.8%). As a second test for confirming ESBL activity in strains with reduced susceptibility to beta-lactams, the inhibitor-potentiated disc diffusion test is therefore a simple and reliable option. 相似文献
17.
The effect of the neuroprotective drug lubeluzole on cortical receptor binding was investigated in animals with photothrombotic ischemic lesions. Control animals were treated with the inactive stereoisomer of the drug. Lubeluzole was applied intravenously as a single bolus (0.31 mg/kg) followed by a 1-h infusion of 0.31 mg/kg. Lubeluzole selectively increased gamma-amino-butyric acid(A) (GABA(A)) receptor binding but had no significant and/or consistent effects on N-methyl-D-aspartate (NMDA), (+/-)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA), and kainate receptors. Lubeluzole caused a significant up-regulation of GABA(A) receptor binding in the lesioned area as well as in unimpaired cortical areas of both hemispheres. This effect appeared in the hours following the lesion and peaked at 24 h. Our findings suggest that reduced cortical excitability brought about by increased binding capacities of GABA(A) receptors may contribute to the neuroprotective effect of lubeluzole. 相似文献
18.
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
19.
Minyu Huang Yi Long Yuzhu Jin Wentong Ya Dongdong Meng Tianzi Qin Lize Su Wei Zhou Jichao Wu Chunhe Huang Qun Huang 《Translational andrology and urology》2021,10(3):1286
BackgroundLong non-coding RNAs (lncRNAs) are essential regulators for various human cancers. However, these lncRNAs need to be further classified for cancer. In the present study, we identified novel competing endogenous RNA (ceRNA) network for bladder cancer (BC) and explored the gene functions of the ceRNA regulatory network.MethodsDifferential gene expression analysis were performed on The Cancer Genome Atlas Urothelial Bladder Carcinoma (TCGA-BLCA) datasets to identify differentially expressed messenger RNAs (mRNAs), lncRNAs, and microRNAs (miRNAs). Based on the competing endogenous RNA (ceRNA) hypothesis, a lncRNA-miRNA-mRNA network was constructed using the StarBase database and visualization by Cytoscape software. Functional enrichment analyses of Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway were performed via R package ClusterProfiler. The protein-protein interaction network was constructed by STRING database and visualization by Cytoscape. Finally, we used CIBERSORT and the TIMER database to analyze the immune infiltrations for BC.ResultsThe regulatory network was constructed via TCGA BLCA cohort. The differential expressions of lncRNA, miRNA, and mRNA were 186, 200, and 2,661, respectively. There were 106 lncRNA, miRNA, and mRNA included in the ceRNA network. In this network, Calcium Voltage-gated Channel Auxiliary Subunit Alpha2delta1 (CACNA2D1, P<0.001), domain containing engulfment adaptor1 (GULP1, P=0.001), latent transforming growth factor beta binding protein 1 (LTBP1, P=0.006), myosin light chain kinase (MYLK, P=0.001), serpin family E member 2 (SERPINE2, P=0.002), spectrin beta non-erythrocytic 2 (SPTBN2, P=0.047), and hsa-miR-590-3p (P<0.001) significantly affected the prognosis of BC patients. Functional enrichment analyses showed that the biological functions included negative regulation of protein phosphorylation, cell morphogenesis, and sensory organ morphogenesis. Important cancer pathways of KEGG included parathyroid hormone synthesis secretion action, the notch signaling pathway, MAPK signaling pathway, the Rap1 signaling pathway, signaling pathways regulating the pluripotency of stem cells, and the transforming growth factor-β signaling pathway. Our findings demonstrated that the ceRNA network has important biological functions and a significant influence on the prognosis of BC.ConclusionsThe lncRNA-miRNA-mRNA network constructed in the present study could provide useful insight into the underlying tumorigenesis of BC, and can determine new molecular biomarkers for the diagnosis and therapeutical treatment of BC. 相似文献
20.
自攻自断螺纹钉在大面积缺损牙保存性修复中的应用 总被引:1,自引:0,他引:1
目的:探讨自攻自断螺纹钉在大面积缺损牙保存性修复中的应用。方法:采用自攻自断螺纹钉,选择凡因龋坏或者外伤使牙体组织损失残缺过大,牙髓未露,活力正常的牙进行修复。结果:本组50例经自攻自断螺纹钉进行固位修复,5年后随访42例,除2例因上颌磨牙牙尖折断而不能修复拔除外,其它40例均达到评判标准,总成功率达95%,结论:自攻自断螺纹钉主要用于对严重缺损而牙髓健康的牙进行保存性修复,还可对要做壳冠修复的牙进行牙壁加固,该方法因材料来源方便,临床效果显著,值得推广。 相似文献