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Liquid based cytology (LBC) has improved cell visualization and preservation in cervical cytology. There has been a reduction in inadequate rate and some data to suggest an increase in sensitivity for dyskaryosis. Training for LBC has focused on differences in distribution of abnormal cells, but in most cases the morphological appearance of the dyskaryotic cells themselves is similar to that seen in conventional cytology. We are describing a new presentation of dyskaryosis which may be a cause of false negative cytology. We have referred to this as 'Bland dyskaryosis' because cells appear deceptively bland on low power examination, and can be misinterpreted as metaplastic or endocervical cells. Bland dyskaryosis cells are seen in groups. The architecture of the group is very disorganized, and adjacent cells show variation in size. Cells have a high nuclear/cytoplasmic ratio and smooth nuclear membranes. Chromatin is finely granular and evenly distributed. This is an unusual presentation of high-grade dyskaryosis and we feel that there is a learning curve in laboratories converting to liquid based cytology. The spectrum of appearances of squamous dyskaryosis needs to be delineated to allow further increases in sensitivity for dyskaryosis.  相似文献   

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Thyroid fine needle aspiration (FNA) is the first choice procedure for differentiating between benign and malignant/suspicious lesions. Despite being highly sensitive and specific, it unfortunately has high inadequacy rates, with false-negatives reported in most series. The fundamental contribution of the aspirator's skill, experience and expertise to inadequacy rates is well documented, differing between both individuals and aspirator groups. We performed a retrospective audit comparing inadequacy rates of cytopathologists and clinicians for all thyroid FNAs performed from 2002–2005 within the Hammersmith Hospitals Trust. A crude cost-effectiveness was estimated, and using histological data where available, positive and negative powers (65.5% and 87.9% respectively), sensitivity (61.5%) and specificity (89.7%) were calculated. Pathologists were found to have significantly ( P  = 0.001) lower inadequacy rates (2.8%) than clinicians (16.1%) and were also more cost-effective (non-significant), with micropapillary carcinomas and lymphomas being identified as the main sources of false-negatives. We thus propose updated protocols to reduce inadequacy and false-negative rates, improve thyroid cancer diagnosis and the quality of patient care within our centre.  相似文献   

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S. Salmasi 《Cytopathology》2006,17(S1):23-24
Cervical cancer accounts for approximately 15% of cancer diagnosed in women worldwide with up to 190 000 deaths per annum. One of the major causes of cervical cancer is the infection of human papillomavirus (HPV), a DNA virus. This virus is epidermotropic; there are over 75 subtypes and subtypes 16, 18, 31 and 33 are associated with cervical intraepithelial neoplasia (CIN) and carcinomas. Since the start of the cervical screening in mid 1960s, the cervical cancer rate has decreased. There are two techniques used for slide preparation and staining: conventional cytology and liquid based cytology (LBC). Due to the differences in sample collection and preparation, certain aspects of cell morphology, architecture and patterns will present differently from each other on the slide. The study was conducted in a County Hospital. Twenty conventional slides and eight LBC slides already reported as ? Glandular neoplasia were reviewed and assessed with regards to their morphological features. Moreover, conventional slides were compared with LBC slides to determine the differences in their cell morphology, sensitivity and specificity. Furthermore, a semi-quantitative method was used and also true-positive and false-positive rates were evaluated using positive predictive value (PPV). The findings indicated that despite the differences in cell morphology there are many similarities between the two techniques. The study also showed that it was difficult to distinguish between abnormal glandular cells and abnormal squamous cells, which may end in a false positive result and over reporting of glandular neoplasia. Finally, it showed that LBC slides were easier to screen and also had a higher positive predictive value (PPV) resulting in higher sensitivity and specificity. In conclusion, the LBC technique is more accurate and conversion to this technique is the positive step in the screening program.  相似文献   

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本文从肌肉系统对大蹼铃蟾和昭觉林蛙进行了观察比较,结果表明这两种无尾两栖类的从存在一定差异。大蹼铃蟾的肌肉结合紧密程度不如昭觉林蛙,且肌肉分节现象较昭觉林蛙了后,以形态-功能-适应三位一体的分析原理为依据,就2个种存在的形态差异,从功能与适应的意义和生物进化地角度两个方面进行了分析和探讨。  相似文献   

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Misplaced confidence in the broad-spectrum antibiotics, increased resistance among previously predictable anaerobic antibiograms, and the push to maximize productivity of available space and downsizing trends has created a need for a simplified cost-effective, and superior method for the isolation and identification of anaerobic bacteria. In this study, the Oxyrase anaerobic plate system which requires no extraneous apparatus to create an anaerobic environment was compared to an anaerobic chamber in the isolation of anaerobic bacteria from 212 consecutive wound specimens. Brucella blood agar and KVL agar plates were used in this comparison study. RapID ANA II, AP120A, special potency disks, and GLC were used for identification. Of the 212 specimens cultured, 87 yielded anaerobic bacteria comprising 182 strains. Thirty-nine strains failed to grow in the anaerobic chamber but grew on the OxyPlates(TM). These strains were predominantly Peptostreptococcus species (28%), Eubacterium species (20%), and Propionibacterium species (20%). Fourteen strains failed to grow on the OxyPlates, but grew in the anaerobic chamber. No trend was noted and all organisms in this category grew on the OxyPlates from other specimens. In conclusion, the Oxyrases anaerobic plate system appears to be an excellent alternative to the conventional anaerobic chamber in the isolation and identification of clinically significant anaerobes found in human samples, obviating the need for separate anaerobic-aerobic workstations, expensive anaerobic apparatus, and additional incubator space.  相似文献   

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Introduction: There is ongoing debate about the terminology used in the classification of dyskaryosis, including whether BNA smears should be classified according to whether koilocytes are present or not. We explored the effect of koilocytosis in the management experiences and clinical outcomes of women with a single BNA smear. Methods: This study includes 410 women aged 20–59 years, resident in Tayside who had an ‘baseline’ BNA smear between 31/10/1999 and 31/10/2002 who were eligible for the TOMBOLA trial but who did not participate. Recommended follow‐up for these women was a repeat smear in six months. Up to three‐years follow‐up data was collected on subsequent cytological smears, colposcopy examinations and any related histology. The baseline smear was re‐read for the presence or absence of koilocytes. Women were classified according to their clinical outcomes during their three years. Results: 47% (192/410) of women were classified as having koilocytosis at baseline. The mean age was lower among these women (25 years) compared to those without koilocytosis (35 years). 55% (105/192) of women with koilocytosis at baseline had one or more negative smears and no further abnormal smears, compared to 63% (137/218) of those without koilocytosis, the difference was not statistically significant. 28% (53/192) of women with koilocytosis at baseline were referred to colposcopy after subsequent low‐grade or high‐grade smears compared to 19% (42/218) of those without koilocytosis; the difference was statistically significant. 14% (27/192) of women with koilocytosis at baseline were diagnosed with CIN2/3 or worse during follow‐up compared to 10% (21/218) of women without koilocytosis; the difference was not statistically significant. Discussion: Our results suggest that the presence or absence of koilocytosis has little impact on the clinical outcomes of women with a BNA smear.  相似文献   

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Many studies have shown that conventional profiling provides reproducible and meaningful results. However, comparison of the technique as used in different countries appears to be nonexistent. In addition, data analysis is often approached differently, and this aspect is also addressed. This paper describes a study to compare the results obtained from profiling milk chocolate samples, using trained panels in Britain and Norway. Data were analyzed using principal component analysis, generalized Procrustes analysis and partial least squares regression. Results indicate that the underlying perceptual structure of the sample spaces obtained from both panels were similar, however, the emphasis on the underlying sensory dimensions differed. Moreover, it was possible to calibrate the two profiles, which has implications for marketing products for export, as well as providing a potential tool for panel monitoring and calibration across cultures.  相似文献   

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Same-different, duo-trio and triangle discrimination methods were compared using vanilla flavored yogurt with and without added sugar as the medium. Two experiments were performed, one in controlled laboratory conditions and the other in conditions approximating more to consumer testing. A modification of the same-different test had greater power than the duo-trio of triangle tests. At higher sugar concentrations, d'values for the three methods were equivalent. Yet, at lower sugar concentrations, the same-different d'tended to be higher. The results are discussed in terms of Sequential Sensitivity Analysis, memory effects and changes between β and criteria.  相似文献   

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Abstract— Radioactive cystathionine, a metabolic precursor of taurine, was injected into the right eye of goldfish. At various times after injection the retina and both optic tecta were extracted with trichloroacetic acid (TCA) and the amount and nature of the radioactivity was determined. Radioactive taurine and inorganic sulfate were present in the TCA-soluble extract of retina and radioactive taurine and a small amount of inorganic sulfate was found in the contralateral optic tectum. That taurine is migrating intraaxonally and is not diffusing in extraaxonal spaces is suggested from experiments in which the migration of taurine was compared with that of [14C]mannitol, used here as a marker of extracellular diffusion. In the time studied (up to 15 h) mannitol did not migrate to the tectum, whereas taurine was detectable in the tectum as early as 8 h after injection. Since intra-axonal diffusion of amino acids and other small molecules in this system has been ruled out, it is likely that taurine is being transported axonally. The axonal transport of taurine was found to be similar to the fast component of protein transport because: (1) their rates of transport are similar, (2) the transport of both is blocked by the protein synthesis inhibitor cycloheximide, (3) vinblastine, which disrupts neurotubules, appears to have similar effects on both protein and taurine transport, and (4) both rapidly transported proteins and taurine remain mostly intra-axonal once they have been transported to the tectum. Taurine and proteins differ in that rapidly transported proteins are primarily paniculate in nature and localized to a large extent in nerve endings, while taurine is primarily in a soluble fraction and is present in nerve endings only in trace amounts. We suggest that taurine may be loosely linked to a newly synthesized protein in the soma and is then transported along with that protein on a similar conveying mechanism in the axoplasm.  相似文献   

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