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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   
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SUMMARY. Samples from 1828 donations were screened for anti-HBc at seven sites in the UK using kits supplied by 10 manufacturers. Only 10 (0.55%) donations were considered to have true anti-HBc reactivity and these were detected by all 10 kits. Additional markers of HBV infection were found in nine of these 10 donations. Additional reactives were found by all kits, the number ranging from 1 to 43.
In the four more specific kits, the 10 true reactives were clearly distinguished from the 'false reactives' by the strength of the reaction. It is concluded that the reliance on a single ELISA test for anti-HBc diagnosis is unwise. The use of a second test known to be more specific than the screening ELISA is recommended.  相似文献   
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Background Exposure of the skin or respiratory tract to proteinases is frequently associated with allergic sensitization. This is of particular significance in the domestic indoor environment where the proteolytic activity of Der p I, the group I allergen of the house dust mite Dermatophagoides pteronyssinus, may influence the allergenicity of mites. Using class-specific proteinase inhibitors and active-site affinity chromatography, we have previously shown that Der p I exhibits a mixed cysteine-serine proteinase activity. Measurement of the amount of cleavage, however, did not determine whether the inhibitors used were targeting exactly the same proteolytic mechanism. Objective To resolve this issue, we have examined whether the cleavage specificity of the cysteine and serine proteinase activities of Der p I was the same. Methods HPLC and mass spectrometry were used to analyse and identify the products of a Der p I-digested peptide substrate and thus identify the peptide bonds cleaved. Results Der p I cleaves different peptide bonds, depending upon the class of proteolytic mechanism used. In the model peptide substrate insulin B chain, the cysteine and serine proteinase activities of Der p I showed preference for glutamic acid and arginine respectively in the P1 position. Conclusion These data suggest the existence of more than one mechanistic form of the allergen immunologically identified as Der p I. If proteolytic activity is indeed a function of allergenicity, this information may have important implications for the pathogenicity of Der p I and the ability of innate antiproteinase defences in the respiratory tract to prevent immune sensitization.  相似文献   
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腕管综合征主要症状体征敏感性与特异性的比较   总被引:5,自引:1,他引:4  
目的 比较腕管综合征 (carpaltunnelsyndrome ,CTS)主要症状、体征的敏感性与特异性。方法 对 10 1例 ( 162只手 )进行症状严重程度与功能状况的询问 ,感觉、运动功能的检查 ;其中 62只手在术后 6周再次测定。结果  162只患手中 15 8只具有典型症状 ( 98% )。Phalen征、前臂正中神经加压征、Semmes Weinstein单丝纤维测试阳性率分别为 98%、96%、82 %。 87%的患手出现肌力下降 ,拇短展肌肌力测定 (定量法 )结果显示 ,与徒手法相比 ,不同性别间、术前与术后的差异均具非常显著意义 (P <0 .0 1)。结论 典型症状、Phalen征、前臂正中神经加压征、拇短展肌肌力变化的敏感性与特异性最高 ,拇短展肌肌力定量法测定是判断腕管综合征严重程度、评定疗效的一个良好的客观指标。  相似文献   
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We have reviewed some of the factors which contribute to lung damage by various toxicants. These include disposition of the chemical, its metabolism, individual cell type susceptibility and the potential for the tissue to repair. We have discussed the use of biochemical parameters to measure the functional activity of individual cell types in order to predict the damage to specific cell types and concluded that careful morphological analysis of lung tissue is likely to provide a more sensitive and informative measure of specific cell type injury. However, in order to investigate the mechanism of toxicity of pulmonary toxicants it is essential to establish the primary biochemical event that leads to cell damage and morphological change. The importance of separating the relevant biochemical change(s) from the cascade of biochemical events associated with dead and dying cells and the reparative response of the lung is emphasised.This report results from a discussion sponsored and organised by the Advisory Subgroup in Toxicology (AST) of the European Science Foundation's Standing Committee for the European Medical Research Councils and held at the Medical Research Council Toxicology Unit, Carshalton, U. K. Those taking part were: W. N. Aldridge (AST; as above); J. Bignon (Unit for Research in Renal and Pulmonary Pathology, University of Paris, Creteil, France); P. H. Burri (Section of Developmental Biology, Institute of Anatomy, University of Berne, Switzerland); G. M. Cohen (as above); D. Dinsdale (MRC Toxicology Unit, Carshalton U. K.); P. Hedqvist (Dept. of Physiology, Karolinska Institute, Stockholm, Sweden); D. Henschler (AST; Dept. of Toxicology and Pharmacology, University of Wurzburg, FDR); G. J. Laurent (Biochemistry Unit, Cardiothoracic Institute, University of London, London, U. K.); R. Lauwerys (AST Industrial and Medical Toxicology Unit, University of Louvain, Brussels, Belgium); F. Lembeck (AST; Dept. for Experimental and Clinical Pharmacology, University of Graz, Austria); N. Lery (AST; Poison Control Centre, Lyon, France); P. Moldeus (Dept. of Forensic Medicine, Karolinska Institute, Stockholm, Sweden); B. Nemery (MRC Toxicology Unit, Carshalton, U. K.); A. Saria (Dept. for Experimental and Clinical Pharmacology, University of Graz, Austria); L. L. Smith (as above);B. Terracini (AST; Dept. of Pathology and Cancer Epidemiology, University of Turin, Italy)  相似文献   
8.
 The objective of the present study was to determine the role of mast cells and histamine in leukocyte-endothelium interactions in mesenteric venules of four rat strains: Brown Norway, Lewis, Sprague-Dawley and Wistar. Intravital microscopy showed that the mast cell stabilizer cromoglycate (5 mg/kg i.v. just before exteriorization of the mesentery) did not affect the baseline level and velocity of leukocyte rolling in any of the four strains. This finding is in agreement with the observation that cromoglycate pretreatment only slightly influenced mast cell degranulation in all strains except the Brown Norway. After mast cell stabilization, only in Sprague-Dawley did topical administration of histamine (10–4 M) result in a significant increase in the level of leukocyte rolling and a decrease in the rolling velocity compared with the time control. Histamine induced leukocyte adhesion only in the Brown Norway strain. In conclusion, the hypothesis presented in other studies, that degranulation of mast cells, and more specifically the release of histamine, is of major importance for the induction of leukocyte-endothelium interactions in rat mesenteric venules is not generally applicable; the present study shows a clear strain dependency. Received: 18 July 1997 / Received after revision: 17 November 1997 / Accepted: 13 March 1998  相似文献   
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According to Sperry's chemoaffinity hypothesis, the projection of a small eye fragment with a reduced amount of optic fibres should be restricted to that position in the optic tectum corresponding to its own specificity. However, previous investigations on different types of quarter-eyes in Xenopus laevis have revealed that their retinal projection was always restricted to the rostral part of the tectum, no matter what the origin of the remaining retinal quadrant. To get an indication of the state of specificity in such eye fragments, we investigated by electrophysiological and histological methods several features of the retinal projections of temporoventral (TV), naso-ventral (NV) and ventral (V) quarter-eyes which referred to their positional identity. Irrespective of their different origins, the projections were always located in the rostral part of the tectum, the size of the innervated tectal area depending for all fragment types on the size of the quarter-eyes, i.e. number of optic fibres. However, quantitative analyses revealed that with increasing eye size the various fragments expand their projections preferentially into those tectal areas that match their original specificity: TV projection is more concentrated in the rostral tectum, NV eyes expand their projections mainly to the caudal tectum, and V eyes enlarge their projections equally into the medial and caudal tectum. In addition, fibre-tracing experiments with cobaltic lysine showed that, according to the different origins of the quarter-eyes, retinal fibres follow the appropriate branch of the optic tract selectively: fibres of NV and V eyes pass mainly through the medial tract, and most fibres of TV eyes innervate the rostral tectum directly from a central position between the two side branches. All these findings suggest that the different types of quarter-eyes retain their original positional identity. Thus, their rostrally located retinotectal projections are not in register with their retinal specificity. We conclude that in X. laevis local positional markers in the tectum, if present at all, do not influence the development of the retinotectal projection. Instead we suggest a concept of self-sorting of the optic fibres, which can account for the partial innervation of the rostral tectum in different types of quarter-eyes.  相似文献   
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During an exposure monitoring study, 78 saw maintenance tradesmen were randomly assigned to be interviewed about their exposures using one of two questionnaire formats: open-ended and partly prompted questions about five categories of materials; and detailed prompting about 75 agents. The more open-ended questionnaire elicited fewer exposure responses overall, but more responses about agents not included on the detailed questionnaire. Composite materials and trade name products were more frequently cited as exposures than individual metals or compounds. Validity of responses was ascertained using air measurements (individual metals) or observations of the employees (composite materials). Sums of sensitivities and specificities were very low (near 1.0) for most of the metals for both types of questionnaire. For composite materials, validity improved substantially. Sensitivities with the partly prompted format (0.44–0.85) were always lower than with detailed prompting (0.80–1.00). Specificities were usually, but not always, higher with partial prompting (0.66–0.92) than with detailed prompting (0.18–0.86). Selection of questionnaire format for an epidemiologic study would depend on the likely prevalence of exposure in controls and the effects of trade-offs in sensitivity and specificity.  相似文献   
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