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71.
R. G. Blanks 《Cytopathology》2011,22(3):146-154
R. G. Blanks
Estimation of disease severity in the NHS cervical screening programme. Part I: artificial cut‐off points and semi‐quantitative solutions Objective: Current cytology and histology classifications are based on ordered categories and have a strong emphasis on providing information that decides a woman's management rather than the best estimate of disease severity. This two‐part paper explores the use of a quantitative approach to both cytology and histology disease severity measurements. Methods: In Part I the problem of artificial cut‐off points is discussed and a simple semi‐quantitative solution to the problem is proposed. This closely relates to the revised British Society for Clinical Cytology (BSCC) terminology. The estimates of disease severity are designed as extensions of the existing methods, with an emphasis on probability rather than certainty, as a more natural way of approaching the problem. Borderline changes are treated as categorical variables, but koilocytosis, mild, moderate and severe dyskaryosis, and ?invasive as quasi‐continuous and the disease severity estimated as a grade number (GN) with any value between 0–4 and the margin of error as a calculated grade range (CGR). Results: As an example, if the reader is unsure between moderate dyskaryosis (HSIL favouring CIN2) and mild dyskaryosis (LSIL favouring CIN1) they can register this uncertainty as a probability, such as 60%/40% moderate/mild. With 2 and 1 as the mid‐points of the grade numbers for moderate and mild dyskaryosis the GN value is ((60 × 2) + (40 × 1))/100 = 1.6. The CGR is 1.5 ? 0.4 to 1.5 + 0.6 = 1.1 to 2.1. The GN (CGR) estimate of disease severity is therefore 1.6 (1.1–2.1). In a similar manner the disease severity from all slides showing koilocytosis or dyskaryosis can be estimated as a number between 0 and 4 with an associated error. Histology can be treated in a similar way. Conclusions: This semi‐quantitative approach provides a framework more suitable for research and audit of disease severity estimates. It avoids the paradox inherent in the current systems using artificial cut‐points to produce categories whereby increasing agreement can only be achieved by losing information.  相似文献   
72.
L. Skoog  E. Tani 《Cytopathology》2011,22(4):215-229
L. Skoog and E. Tani Immunocytochemistry: an indispensable technique in routine cytology Immunocytology is today accepted as an indispensable adjunct to cytomorphology. It has led to a dramatic increase in diagnostic accuracy and also allowed the identification of markers both for prognosis and targeted therapies. Most commercially available antibodies will perform in a reproducible and reliable way provided that the cytological specimen has been prepared and fixed properly. In this review various aspects of immunocytochemistry such as preparation of cytological specimens, fixation and choice of antibodies will be discussed. The specificity of the most commonly used antibodies is summarized and staining panels for various tumours are suggested. In addition, the use of markers for targeted therapy and theranostics is discussed, as well as a brief section on the identification of infectious agents.  相似文献   
73.
There is growing evidence that molecular testing is feasible on all types of cytological preparation, which is fortunate as more diagnostic markers and biomarkers for targeted therapies are discovered for use in pulmonary and pleural malignancies. In this article we will discuss the pre-analytic, analytic, and post-analytic (interpretive) considerations for successful implementation of molecular tests for diagnostic and predictive markers in respiratory and pleural cytology. The vast majority of laboratories are familiar with, and have validated their molecular protocols for, formalin-fixed paraffin-embedded surgical specimens, which are not directly applicable to cytology specimens. Thus, rigorous validation must be performed for each type of fixative and cytology preparation before it is implemented in the clinical setting.  相似文献   
74.
Analysis of telomerase activity and detection of its catalytic subunit,hTERT   总被引:16,自引:0,他引:16  
The discovery of the enzyme telomerase and its subunits has led to major advances in understanding the mechanisms of cellular proliferation, immortalization, aging, and neoplastic transformation. The expression of telomerase in more than 85% of tumors provides an excellent tool for the diagnosis, prognosis, and treatment of cancer. However, the techniques employed in its detection appear to play a significant role in the interpretation of the results. The telomeric repeat amplification protocol (TRAP assay) has been the standard assay in the detection of telomerase activity and many variations of this technique have been reported. Recent advances in the development of the TRAP assay and the incorporation of techniques that provide a quantitative and qualitative estimate of telomerase activity are assessed in this review. In addition to histological and cytological examination of tissues, distribution patterns of the catalytic subunit of telomerase, hTERT, are frequently used in the prognosis of tumors. The methods involved in the detection of hTERT as a biomarker of cellular transformation are also analyzed.  相似文献   
75.
目的:探讨血流阻断的缺血预处理技术在肝癌切除术中的临床应用价值。方法:选取2010年4月至2013年7月我院收治的96名原发性肝癌并采用肝脏部分切除术进行治疗的患者,将患者随机分为观察组和对照组,每组各48例,观察组在肝脏部分切除术阻断肝门血流前先分别给予1个5 min缺血和再灌注的处理。对照组不采取任何干预措施。术前、术后1天、3天、7天时分别进行生化检查,并于术前及术后1h对Fas-mRNA表达、Caspasc-3活性及AI进行测定,观察记录患者术后的并发症情况、手术时间、术中出血量以及住院时间。结果:术后1天、3天、7天时两组间的AST、ALT、TBIL等生化指标的含量情况相比,观察组均显著优于对照组(P0.05);术后l d,两组患者ALB均有不同程度的降低,对照组低于观察组(P0.05);术后住院时间观察组为13.28±3.85天,对照组为19.48±4.92天,观察组明显低于对照组(P0.05);术后1h,两组患者的Fas-mRNA表达、Caspasc-3活性相比于阻断前均显著提高,但观察组提高幅度明显低于对照组,差异有统计学意义(P0.05);两组阻断前均未见肝细胞凋亡,术后l h时,两组组均可见肝细胞凋亡,且对照组明显高于观察组组(P0.05)。结论:血流阻断的缺血预处理技术具有操作简便、副作用小的重要特点,应用于肝癌切除术中在保护肝功能方面具有显著的优势。  相似文献   
76.
Quantitative proteomics combined with immuno-affinity purification, SILAC immunoprecipitation, represent a powerful means for the discovery of novel protein:protein interactions. By allowing the accurate relative quantification of protein abundance in both control and test samples, true interactions may be easily distinguished from experimental contaminants. Low affinity interactions can be preserved through the use of less-stringent buffer conditions and remain readily identifiable. This protocol discusses the labeling of tissue culture cells with stable isotope labeled amino acids, transfection and immunoprecipitation of an affinity tagged protein of interest, followed by the preparation for submission to a mass spectrometry facility. This protocol then discusses how to analyze and interpret the data returned from the mass spectrometer in order to identify cellular partners interacting with a protein of interest. As an example this technique is applied to identify proteins binding to the eukaryotic translation initiation factors: eIF4AI and eIF4AII.  相似文献   
77.
王梅  单际修 《植物学通报》2000,17(2):141-149
CP43和CP47是构成光合生物内周天线的两个重要的色素蛋白复合物,在生物体内主要起着传递激发能的作用。最近,大量研究证明,它们在放氧等过程中也起着重要作用。因此,近年来人们借助各种先进的研究技术对它们的结构进行了探讨,以揭示它们行使不同生理功能的分子机理。分子生物学技术可以使人们在整体水平上研究蛋白复合物的结构与功能,因此是一个非常有用的研究手段。本文即对近年来人们通过分子生物手段,以蓝藻为转化  相似文献   
78.
Although the theoretical capacity of silicon is ten times higher than that of graphite, the overall electrode capacity of Si anodes is still low due to the low Si loading and heavy metal current collector. Here, a novel flexible 3D Si/C fiber paper electrode synthesized by simultaneously electrospraying nano‐Si‐PAN (polyacrylonitrile) clusters and electrospinning PAN fibers followed by carbonization is reported. The combined technology allows uniform incorporation of Si nanoparticles into a carbon textile matrix to form a nano‐Si/carbon composite fiber paper. The flexible 3D Si/C fiber paper electrode demonstrate a very high overall capacity of ≈1600 mAh g‐1 with capacity loss less than 0.079% per cycle for 600 cycles and excellent rate capability. The exceptional performance is attributed to the unique architecture of the flexible 3D Si/C fiber paper, i.e., the resilient and conductive carbon fiber network matrix, carbon‐coated Si nanoparticle clusters, strong adhesion between carbon fibers and Si nanoparticle clusters, and uniform distribution of Si/C clusters in the carbon fiber frame. The scalable and facile synthesis method, good mechanical properties, and excellent electrochemical performance at a high Si loading make the flexible 3D Si/C fiber paper batteries extremely attractive for plug‐in electric vehicles, flexible electronics, space exploration, and military applications.  相似文献   
79.
In this study, we present an adaptive anisotropic finite element method (FEM) and demonstrate how computational efficiency can be increased when applying the method to the simulation of blood flow in the cardiovascular system. We use the SUPG formulation for the transient 3D incompressible Navier–Stokes equations which are discretised by linear finite elements for both the pressure and the velocity field.

Given the pulsatile nature of the flow in blood vessels we have pursued adaptivity based on the average flow over a cardiac cycle. Error indicators are derived to define an anisotropic mesh metric field. Mesh modification algorithms are used to anisotropically adapt the mesh according to the desired size field. We demonstrate the efficiency of the method by first applying it to pulsatile flow in a straight cylindrical vessel and then to a porcine aorta with a stenosis bypassed by a graft. We demonstrate that the use of an anisotropic adaptive FEM can result in an order of magnitude reduction in computing time with no loss of accuracy compared to analyses obtained with uniform meshes.  相似文献   
80.
We here in report the synthesis of gold nanoparticles (AuNPs) using a Crinum macowanii bulb water extract. The as‐synthesized AuNPs were characterized using ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, X‐ray diffraction, transmission electron microscopy, and a zeta potential‐sizer. The results showed that the as‐synthesized AuNPs were crystalline and mostly spherical in shape with a small mixture of triangular, tetrahedral, hexagonal, octagonal, and diamond shapes. The as‐synthesized AuNPs together with those synthesized by conventional methods were subsequently used as enhancers for the luminol signal in blood detection. It was noted that the AuNPs synthesized from the Crinum macowanii bulb water extract could enhance the chemiluminescence signal for blood detection by luminol to the same extent as AuNPs prepared by conventional methods. Furthermore, both types of AuNPs served as fluorescence enhancers for blood detection when luminol was replaced with the bulb water extract.  相似文献   
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