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排序方式: 共有881条查询结果,搜索用时 15 毫秒
1.
Background:We aim to evaluate the efficiency of Raman spectroscopy (RS) in diagnosing suspected patients with intrahepatic cholangiocarcinoma (ICC), manifested by diagnostic sensitivity, specificity, and accuracy.Methods:We will research widely the articles concerning the use of RS in ICC through authenticated database including PubMed/Medline, EMBASE, Web of Science, Ovid, Web of Knowledge, Cochrane Library, and CNKI between January 2012 and November 2020, retrieving at least 1500 spectra with strict criteria. This study will be carried out in accordance to Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. We are going to summarize the test performance using random effects models.Results:Based on the pooled sensitivity, specificity, and diagnostic accuracy, we intend to provide the relative diagnostic efficiency in ICC through RS.Conclusion:Through this systematic review and meta-analysis, we intend to provide the pooled sensitivity, specificity and diagnostic accuracy of RS in the diagnosis of suspected ICC. Other parameters like positive likelihood ratios (LR), negative LR, diagnostic odds ratio (DOR), and area under curve (AUC) of the summary receiver operating characteristics (SROC) curve will also be calculated and related figures will be drawn to help illustrate the efficacy of RS in the diagnosis of ICC. 相似文献
2.
The cellular mechanisms underlying hereditary photoreceptor degeneration are still poorly understood, a problem that is exacerbated by the enormous genetic heterogeneity of this disease group. However, the last decade has yielded a wealth of new knowledge on degenerative pathways and their diversity. Notably, a central role of cGMP-signalling has surfaced for photoreceptor cell death triggered by a subset of disease-causing mutations.In this review, we examine key aspects relevant for photoreceptor degeneration of hereditary origin. The topics covered include energy metabolism, epigenetics, protein quality control, as well as cGMP- and Ca2+-signalling, and how the related molecular and metabolic processes may trigger photoreceptor demise. We compare and integrate evidence on different cell death mechanisms that have been associated with photoreceptor degeneration, including apoptosis, necrosis, necroptosis, and PARthanatos. A special focus is then put on the mechanisms of cGMP-dependent cell death and how exceedingly high photoreceptor cGMP levels may cause activation of Ca2+-dependent calpain-type proteases, histone deacetylases and poly-ADP-ribose polymerase. An evaluation of the available literature reveals that a large group of patients suffering from hereditary photoreceptor degeneration carry mutations that are likely to trigger cGMP-dependent cell death, making this pathway a prime target for future therapy development.Finally, an outlook is given into technological and methodological developments that will with time likely contribute to a comprehensive overview over the entire metabolic complexity of photoreceptor cell death. Building on such developments, new imaging technology and novel biomarkers may be used to develop clinical test strategies, that fully consider the genetic heterogeneity of hereditary retinal degenerations, in order to facilitate clinical testing of novel treatment approaches. 相似文献
3.
Tom Lindfors Carita Kvarnström Ari Ivaska 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2002,518(2):131-138
Electrically conducting soluble polyaniline (PANI), containing different amounts of a bulky lipophilic cationic additive, tridodecylmethylammonium chloride (TDMACl), was studied by Raman (λexc=780 nm) and UV–vis spectroscopy. PANI was made simultaneously electrically conducting and soluble with bis[4-(1,1,3,3-tetramethylbutyl)phenyl]phosphoric acid in dichloromethane. The PANI membranes were prepared by drop casting on glassy carbon or ITO substrates. Raman and UV–vis measurements were carried out in a 0.1 M CaCl2 solution at potentials between 400 and ?600 mV (vs. SCE) at pH 6, or alternatively at the open circuit potential at pH 10. The results of Raman, UV–vis and cyclic voltammetric measurements confirm that the incorporation of TDMACl into the PANI membrane facilitates the oxidation and reduction of PANI. 相似文献
4.
Salahudeen Abdulla K.; Wang Chunyou; Bigler Steven A.; Dai Zhongyi; Tachikawa Hiroyasu 《Nephrology, dialysis, transplantation》1996,11(4):635-642
BACKGROUND AND PURPOSE.: Heme-proteins, besides causing renal tubular obstruction, maycontribute to rhabdomyolysis-induced renal injury through aheme-iron-mediated lipid peroxidation process. In the presentstudy, we compared the combined therapy of a lipid peroxidationinhibitor, 21-aminosteroid (21-AS) and fluid-alkaline-mannitol(FAM) diuresis with either of them alone to determine the efficacyof the combination therapy and to delineate the roles of lipidperoxidation and cast formation. METHODS AND RESULTS.: Employing Raman spectroscopy, we confirmed in vitro the abilityof 21-AS to inhibit iron-induced fatty acid peroxidation. 21-ASwas then administered to rats developing renal failure fromglycerol-induced rhabdomyolysis. Although 21-AS inhibited rhabdomyolysis-inducedplasma and renal lipid peroxidation, renal protection was incomplete.Administration of FAM to inhibit cast formation afforded a betterrenal protection. However, when these therapies were combinedto inhibit both lipid peroxidation and cast formation, therewas a synergistic renal functional protection. This was accompaniedby a maximum inhibition of renal and plasma lipid peroxidation,as well as, renal tubular necrosis and cast formation. Comparedto combination therapy, FAM therapy alone, despite identicalvolume, was accompanied by a higher tubular necrosis and castformation. CONCLUSIONS.: That combining a lipid peroxidation inhibitor with fluid-alkalinediuresis in rhabdomyolysis further lowers renal lipid peroxidation,tubular necrosis and cast formation and synergistically limitsrenal dysfunction (i) supports a role for lipid peroxidationin the pathophysiology of rhabdomyolysis ARF, (ii) underscoresthe role of intratubular heme retention, a cause for tubularobstruction as well a source for prodigious amount of iron,likely involved in the lipid peroxidation, and (iii) raisesthe possibility of interactions between non-oxidant and oxidantmechanisms. 相似文献
5.
从中药的整体性出发,开展中药拉曼谱图与其寒热药性的相关性分析,并对中药寒热药性进行统计判别研究。本研究选取寒凉性中药109种、温热性中药128种,共计237种中药;经样品前处理后,利用如海光电SEED 3000近红外拉曼光谱仪进行检测,得到每味中药的拉曼谱图;并对量化后的中药拉曼数据进行特征筛选和统计检验,筛选出与寒热药性密切相关的特征拉曼位移及其峰强,然后基于5种算法进行寒热药性的判别建模。经比较分析发现,相较于其他模型,随机森林(RF)模型展现出最佳的效果,对测试集判别的正确率高于90%,曲线下面积(AUC)和精确度大于0.90。本研究基于大样本量中药的分析,中药的拉曼数据与其寒热药性之间具有显著的相关性,可作为药性表征指标,结合RF算法进行寒热药性的判别分析。 相似文献
6.
Diagnostic accuracy of Raman spectroscopy for prostate cancer: a systematic review and meta-analysis
Jae Joon Park Do Kyung Kim Soomin Lee Yoonseo Choi Yon Hee Kim Joon-Ho Lee Ki Hyun Kim Jae Heon Kim 《Translational andrology and urology》2021,10(2):574
BackgroundAlthough various studies have been conducted to demonstrate the possibility of Raman spectroscopy (RS) as a diagnostic tool for prostate cancer (PC), it is difficult to use it in the real clinical area because of imitations in various research processes. Therefore, we did a systematic review and meta-analysis about the accuracy in diagnostic use of RS for PC.MethodsA literature search was done using PubMed, Embase, and Cochrane library databases in March 2019 to analyze the accuracy of RS for diagnosis of PC. The accuracy of RS for diagnosis of PC was evaluated by means of pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and summary receiver operating characteristic (SROC).ResultsFive studies were included for qualitative analysis by screening the remaining articles according to the inclusion and exclusion criteria by means of a systematic review. The pooled sensitivity and specificity of RS were 0.89 (95% CI: 0.87–0.91) and 0.91 (95% CI: 0.89–0.93), respectively. The overall PLR and NLR were 9.12 (95% CI: 4.15–20.08) and 0.14 (95% CI: 0.07–0.29), respectively. The DOR of RS demonstrated high accuracy (73.32; 95% CI: 18.43–291.73). The area under the curves (AUCs) of SROC curves was 0.93.ConclusionsRS is an optical diagnostic method with high potential for diagnosis and grading of PC and has advantages of real-time and convenient use. In order to consider real-time use of RS in an actual clinical setting, more studies for standardization and generalization of RS performance and analytical method must be conducted. 相似文献
7.
8.
目的研究水杨酸、对甲氧基苯甲酸和甲硝唑等化合物拉曼光谱的波长选择性。方法分别采用近红外、可见和紫外区3种波长的激光激发获得不同的拉曼光谱,受照样品包括水杨酸、对甲氧基苯甲酸以及临床常用药物甲硝唑。结果水杨酸、对甲氧基苯甲酸的水溶液在可见和近红外激发下无法获得任何拉曼信息,但在紫外激发下可获得信息丰富的拉曼光谱,且与其固体拉曼谱对应良好。而甲硝唑在紫外激发下没有明显的拉曼峰但在近红外和可见光激发下能获得一致的拉曼信息。结论水杨酸、对甲氧基苯甲酸水溶液的拉曼光谱证明了紫外激发的优越性,甲硝唑的拉曼光谱提示样品对激发波长的选择性。 相似文献
9.
The inclusion complex of diclofenac sodium (DCFNa) and β-cyclodextrin (βCD) was prepared and analyzed by using Raman and SERS spectroscopy. The interaction between DCFNa and βCD molecules was evidenced by monitoring the change in the peak positions and the widths of some guest molecule bands relative to those observed in the spectra of the free compound and 1:1 DCFNa–βCD physical mixture. Raman data have shown that the interaction between the guest and host molecules in the 1:1 DCFNa–βCD complex is maintained both through the dichlorophenyl ring and the phenylacetate group. SER spectra revealed that depending on the pH value of the solution different isomeric forms of the 1:1 guest–host complex are preferentially adsorbed on the silver surface via the nonbonding electrons of the oxygen atom. The orientation of the adsorbed species with respect to the metal surface was also elucidated. 相似文献
10.
《Expert review of anticancer therapy》2013,13(4):359-360
Brain tumor surgery is one of the key factors in prolonging survival in patients with low- and high-grade gliomas. However, resections of these infiltrative lesions have historically been limited by the inability to accurately detect tumor margins. New methods in microscopy and dye injection have enabled more complete resections, but continue to lack biochemical specificity or high-resolution image acquisition. Stimulated Raman scattering microscopy represents an improvement over past techniques in the ability to differentiate intraparenchymal tissues on the basis of biochemical attributes, and is available for use in real-time, a feature that facilitates its translation to the surgical setting. 相似文献