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91.
We prove two results about the problem of finding the Helly number for line transversals to a family of parallel triangles in the plane: (1) If each three triangles of a family of parallel right triangles are intersected by an ascending (or a descending) line, then there is an ascending (or a descending) line that intersects all  相似文献   
92.
当知道一个奖惩系统的等级和保费水平时,利用信息熵提出并得到奖惩系统的理想概率分布.在保单中考虑人身伤亡索赔次数的二元模型,将奖惩系统的平稳概率分布与理想概率分布的差异,通过卡方值与多余度分别表现出来,将其作为评价奖惩系统的一个新工具.  相似文献   
93.
    
A new device to prevent erroneously focused shock waves to the renal parenchyma during extracorporeal shock wave lithotripsy (ESWL) has been developed; an anti-miss-shot control device (AMCD) and experiments have been conducted to evaluate its effectiveness. For shock wave generation and stone localization, piezoceramic elements (PSE) and ultrasound localization, respectively were used. After stone localization, probing ultrasounds (PU) were emmitted from the PSE towards the focal region and the reflected sound levels (RSL) were monitored by the PSE which also functioned as a microphone. A direct hit by the PU to the stone or a miss was judged from the RSL, i.e. a high RSL indicates a direct hit and a low RSL indicates a miss. Shock waves were generated only when the RSL exceeded the level which indicated a direct hit. The experimental results showed that the injury to the renal parenchyma was decreased by using the AMCD. Clinical application of the AMCD is expected to increase the safety of ESWL.This article was processed using Springer-Verlag TEX Shock Waves macro package 1990.  相似文献   
94.
通过对寄生虫与宿主的相互关系及影响因素进行研究,以有效地控制寄生虫病的发生.结果:不同种类的寄生虫具有不同的亲和性,可在机体的不同脏器或组织寄生.当有两种或两种以上的寄生虫感染时,它们通过相互协同或相互拮抗,共同参与寄生虫抗宿主反应,引起机械性损伤、营养不良、变态反应等.同时,机体对入侵的寄生虫产生一系列免疫反应,及时清除入侵的寄生虫,并具有抵抗再感染的能力,或形成免疫耐受.  相似文献   
95.
    
Artemisia argyi H.Lév. & Vaniot essential oil (AAEO) has shown pharmacological effects such as anti-inflammation, antioxidant, and anti-tumor properties. However, the protective effect of AAEO on lipopolysaccharide (LPS)-induced liver injury and its potential protective mechanism are still unclear. In this study, we used ultra-performance liquid chromatography tandem mass spectrometry metabolomics techniques to investigate the changes in liver tissue metabolites in mice exposed to LPS with or without AAEO treatment for 14 days. The biochemical results showed that compared with the control group, AAEO significantly reduced the levels of liver functional enzymes, suggesting a significant improvement in liver injury. In addition, the 18 differential metabolites identified by metabolomics were mainly involved in the reprogramming of arachidonic acid metabolism, tryptophan metabolism, and purine metabolism. AAEO could significantly inhibit the expression of COX-2, IDO1, and NF-κB; enhance the body's anti-inflammatory ability; and alleviate liver injury. In summary, our study identified the protective mechanism of AAEO on LPS-induced liver injury at the level of small molecular metabolites, providing a potential liver protective agent for the treatment of LPS-induced liver injury.  相似文献   
96.
    
Qingxuan Zhike granules (QXZKG), a traditional Chinese patent medication, has shown therapeutic potential against acute lung injury (ALI). However, the precise mechanism underlying its lung-protective effects requires further investigation. In this study, integrated network pharmacology, molecular docking, and lipidomics were used to elucidate QXZKG's regulatory effect on lipid metabolism in lipopolysaccharide-induced ALI. Animal experiments were conducted to substantiate the efficacy of QXZKG in reducing pro-inflammatory cytokines and mitigating pulmonary pathology. Network pharmacology analysis identified 145 active compounds that directly targeted 119 primary targets of QXZKG against ALI. Gene Ontology function analysis emphasized the roles of lipid metabolism and mitogen-activated protein kinase (MAPK) cascade as crucial biological processes. The MAPK1 protein exhibited promising affinities for naringenin, luteolin, and kaempferol. Lipidomic analysis revealed that 12 lipids showed significant restoration following QXZKG treatment (p < 0.05, FC >1.2 or <0.83). Specifically, DG 38:4, DG 40:7, PC O-40:8, TG 18:1_18:3_22:6, PI 18:2_20:4, FA 16:3, FA 20:3, FA 20:4, FA 22:5, and FA 24:5 were downregulated, while Cer 18:0;2O/24:0 and SM 36:1;2O/34:5 were upregulated in the QXZKG versus model groups. This study enhances our understanding of the active compounds and targets of QXZKG, as well as the potential of lipid metabolism in the treatment of ALI.  相似文献   
97.
    
Reliable methods for the determination of tryptophan and its metabolites are vital to the monitoring of biochemical states during the initiation and progression of cardiovascular disease. In the present study, a single‐run liquid chromatography–tandem mass spectrometry (LC‐MS/MS) method was developed for the simultaneous determination of tryptophan (Trp) and its metabolites, including kynurenine (Kyn), kynurenic acid (KA), xanthurenic acid (XA) and 5‐hydroxytryptamine (5‐HT), in human plasma. The plasma samples were prepared using a protein precipitation approach, and the chromatographic separation was performed by gradient elution on a C18 column within a total analysis time of 3.5 min. The calibration ranges were 40–20,000 ng/mL for Trp, 4–2000 ng/mL for Kyn, 0.2–100 ng/mL for KA, 0.4–200 ng/mL for XA and 1–500 ng/mL for 5‐HT, and the precision and accuracy were acceptable. The evaluation of recovery and internal standard‐normalized matrix effect proved that the sample preparation approach was effective and the matrix effect could be negligible. The newly developed method was successfully applied to the analysis of plasma samples from healthy individuals and myocardial infarction patients. The findings suggested that the plasma concentrations of Trp, Kyn, 5‐HT as well as the concentration ratios of Kyn/Trp and Trp/5‐HT might serve as biomarkers for the monitoring of acute myocardial infarction.  相似文献   
98.
    
This study aimed to investigate the efficacy of mangiferin, including its known antioxidant and anti‐inflammatory effects on sepsis‐induced lung injury induced by a classical cecal ligation and puncture (CLP) models in mouse using a metabolomics approach. A total of 24 mice were randomly divided into four groups: the sham group was given saline before sham operation. The CLP group received the CLP operation only. HMF and LMF groups were given mangiferin treatment of high dose and low dose of mangiferin, respectively, before the CLP operation. One week after treatment, the mice were sacrificed and their lungs were collected for metabolomics analysis. We developed ultra‐performance liquid chromatography coupled with quadrupole‐time‐of‐flight mass spectrometry to perform lung metabolic profiling analysis. With the methods of principal component analysis and partial least squares discriminant analysis, 58 potential metabolites associated with amino acid metabolism, purine metabolism, lipid metabolism and energy regulation were observed to be increased or reduced in HMF and LMF groups compared with the CLP group. Conclusively, our results suggest that mangiferin plays a protective role in the moderation of sepsis‐induced lung injury through reducing oxidative stress, regulating lipid metabolism and energy biosynthesis.  相似文献   
99.
    
A ternary complex comprising plasmid DNA, lipopolysaccharide‐binding peptide (LBP), and deoxycholic acid‐conjugated polyethylenimine (PEI‐DA) is prepared for combinational therapy of acute lung injury (ALI). The LBP is designed as an anti‐inflammatory peptide based on the lipopolysaccharide (LPS)‐binding domain of HMGB‐1. In vitro cytokine assays show that LBP reduces levels of proinflammatory cytokines by inhibiting LPS. PEI‐DA is synthesized as the gene carrier by conjugation of deoxycholic acid to low‐molecular weight polyethylenimine (2 kDa, PEI2k). PEI‐DA has higher transfection efficiency than high‐molecular weight polyethylenimine (25 kDa, PEI25k). The ternary complex of an HO‐1 plasmid (pHO‐1), PEI‐DA, and LBP is prepared as a combinational system to deliver the therapeutic gene and peptide. The transfection efficiency of the ternary complex is higher than that of the pHO‐1/PEI‐DA binary complex. The ternary complex also reduces TNF‐α secretion in LPS‐activated Raw264.7 macrophage cells. Administration of the ternary complex into the lungs of an animal ALI model by intratracheal injection induces HO‐1 expression and reduces levels of proinflammatory cytokines more efficiently than the pHO‐1/PEI‐DA binary complex or LBP alone. In addition, the ternary complex reduces inflammation in the lungs. Therefore, the pHO‐1/PEI‐DA/LBP ternary complex may be an effective treatment for ALI.

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100.
    
Lipids represent biologically ubiquitous and highly dynamic molecules in terms of abundance and structural diversity. Whereas the potential for lipids to inform on disease/injury is promising, their unique characteristics make detection and identification of lipids from biological samples analytically demanding. We report the use of ultraperformance convergence chromatography (UPC2), a variant of supercritical fluid chromatography, coupled to high‐resolution, data‐independent tandem mass spectrometry for characterization of total lipid extracts from mouse lung tissue. The UPC2 platform resulted in lipid class separation and when combined with orthogonal column chemistries yielded chromatographic separation of intra‐class species based on acyl chain hydrophobicity. Moreover, the combined approach of using UPC2 with orthogonal column chemistries, accurate mass measurements, time‐aligned low‐ and high‐collision energy total ion chromatograms, and positive and negative ion mode product ion spectra correlation allowed for confident lipid identification. Of great interest was the identification of differentially expressed ceramides that were elevated 24 h post whole thorax lung irradiation. The identification of lipids that were elevated 24 h post‐irradiation signifies a unique opportunity to investigate early mechanisms of action prior to the onset of clinical symptoms in the whole thorax lung irradiation mouse model.  相似文献   
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