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OBJECTIVE: To standardize the automated measurement of fractal dimension on cytologic smears and compare the fractal dimension of benign and malignant breast cells and cervical lesions on cytologic material to evaluate its role in the discrimination of benign from malignant cells. STUDY DESIGN: We randomly selected fine needle aspiration cytology smears of 42 cases of infiltrating duct carcinoma and 38 cases of fibroadenoma of the breast. Similarly, 16 cervical carcinoma and 20 normal cervical smears were selected for study. Ten cells were selected randomly from each case. Box counting of fractal dimension of malignant and benign cells was achieved with an image cytometer (Leica, Cambridge, England) using Quantimet 600 software (Leica). Then a well-spaced grid with multiple small boxes of a particular pixel length was superimposed on the cell. The dimension of the box was selected as 4, 8 and 16 pixels. With the help of a logical "AND" operation, we counted the number of boxes touching the peripheral margin of the cell nuclei. For each cell, the log-log graph of 1 per box size was plotted against the number of boxes touching the peripheral rim of the cell. The slope of each graph was identified using the least-squares method of regression analysis. RESULTS: The mean fractal dimension of malignant cells was 0.8536 +/- 0.1120 as compared to 0.8403 +/- 0.1115 in benign cell groups. The Mann-Whitney U test showed a significant difference in fractal dimension in these 2 groups (P = .05). The mean fractal dimension of malignant cells from the cervix was 0.8656 +/- 0.1499 as compared to 0.8315 +/- 0.1312 in benign cells. The Mann-Whitney U test showed a significant difference in fractal dimension in these 2 groups (P < .02). CONCLUSION: Fractal dimension may be a helpful adjunctive technique to discriminate between benign and malignant cells.  相似文献   
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Motor behaviors require animals to coordinate neural activity across different areas within their motor system. In particular, the significant processing delays within the motor system must somehow be compensated for. Internal models of the motor system, in particular the forward model, have emerged as important potential mechanisms for compensation. For motor responses directed at moving visual objects, there is, additionally, a problem of delays within the sensory pathways carrying crucial position information. The visual phenomenon known as the flash-lag effect has led to a motion-extrapolation model for compensation of sensory delays. In the flash-lag effect, observers see a flashed item colocalized with a moving item as lagging behind the moving item. Here, we explore the possibility that the internal forward model and the motion-extrapolation model are analogous mechanisms compensating for neural delays in the motor and the visual system, respectively. In total darkness, observers moved their right hand gripping a rod while a visual flash was presented at various positions in relation to the rod. When the flash was aligned with the rod, observers perceived it in a position lagging behind the instantaneous felt position of the invisible rod. These results suggest that compensation of neural delays for time-varying motor behavior parallels compensation of delays for time-varying visual stimulation.  相似文献   
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OBJECTIVE: To investigate the relevance of image analysis for grading breast carcinoma. STUDY DESIGN: Twenty-five ductal breast carcinoma cases were chosen randomly from routine fine needle aspiration clinics. The results of cytomorphologic grading and image morphometry were correlated with those of histologic grading. The five image morphometric parameters studied were nuclear diameter, nuclear area, nuclear roundness, nuclear perimeter and grey level to compare with chromatin texture. RESULTS: Cytologic grading alone had a high correlation with histologic grading. The lowest correlation was found in grade 2 tumors. When cytologic grading was supplemented with image morphometric parameters, the correlation was higher than that of cytologic grading alone. CONCLUSION: Cytologic grading has a high correlation with histologic grading. The correlation improves further on supplementation with image morphometric parameters.  相似文献   
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OBJECTIVE: To investigate the relevance of nuclear morphometry in separating the categories of "fibroadenoma" and "fibroadenoma with atypia." STUDY DESIGN: Thirty consecutive breast lumps, on which a fine needle aspiration (FNA) diagnosis of fibroadenoma was followed by excision and histopathologic confirmation of the diagnosis, were included. Atypia on cytology was based on cell overlap, nuclear enlargement and cell dyscohesion. Nuclear morphometric comparison was carried out between the categories of fibroadenoma, fibroadenoma with atypia and grade 1 ductal carcinoma cases that formed part of an earlier study. The parameters employed were area, roundness, diameter, perimeter and grey level. RESULTS: Among the 30 cases of fibroadenoma reported on FNA, an additional component of atypia was noted in 5. On subsequent histopathology, atypia was not confirmed in any of the cases. On morphometric analysis, a significant difference was noted between fibroadenoma and fibroadenoma with atypia categories, as between fibroadenoma and grade 1 ductal carcinoma cases. However, no significant difference was noted between fibroadenoma with atypia and grade 1 ductal carcinoma cases. CONCLUSION: FNA assessment of atypia in cases of fibroadenoma is difficult. Even conventional nuclear morphometry, though supporting the initial impression of atypia, does not help with this assessment. Also, based on morphometry alone, there may be difficulty separating fibroadenomas with atypia and grade 1 ductal carcinomas. Larger studies, employing other morphometric parameters, such as chromatin texture and fractal dimension, may shed further light on the subject.  相似文献   
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OBJECTIVE: To compare cytomorphology preservation and immunohistochemistry results between conventional cell blocks (CCB) and cytoscrape cell blocks (SCB). STUDY DESIGN: Fine needle aspiration (FNAC) was done in 17 consecutive cases. Air-dried smears for May-Grünwald-Giemsa stain and wet-fixed smear for hematoxylin-eosin (H-E) stain were prepared. Simultaneously another pass was made in each case for preparation of material for CCB. One of the H-E-stained smears was spared for SCB. SCB was compared with CCB for cell morphology. Immunostaining was performed both cell blocks, as well as on FNA smears in 8 cases. Results were evaluated for intensity of staining and percentage of cells showing positivity. RESULTS: CCB and SCB sections showed adequate cellularity in all cases. Morphologic preservation was good in SCB sections. There was good architectural and nuclear preservation in all cases of SCB. Immunostaining results showed better and clear intensity of staining with little background in all cell block cases. CONCLUSION: SCB is a valuable technique in cell blocks from stained FNA smears. The cytomorphologic details are equally good in SCB and CCB. Additional panels of immunostaining can be done on SCB for better diagnosis and classification, particularly in cases in which repeat FNA is not possible.  相似文献   
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Objectives:  To perform an audit of all smears reported as atypical glandular cells (AGC) using the Bethesda system (TBS) 2001.
Methods:  A total of 18 376 cervical smears were screened from January 2005 to June 2007, of which 65 cases were reported as AGC. Follow-up histology was available in 31 cases (47.7%), in whom a detailed cytological/histological correlation was carried out.
Results:  AGC constituted 0.35% of all Pap smears. Follow-up histology was normal or benign in 20 cases, whereas a squamous or glandular abnormality was seen in 11 cases. Squamous abnormalities included one case each of cervical intraepithelial neoplasia (CIN)1, CIN2 and CIN3 and five cases of squamous cell carcinoma. All glandular epithelial abnormalities were endometrial in origin and included two endometrial adenocarcinomas and one uterine serous carcinoma. Neither in situ nor invasive adenocarcinoma of the endocervix was observed. Review of smears and reclassification as AGC, not otherwise specified and favour neoplasia revealed a higher proportion of abnormality in the latter group, reaffirming the utility of subtyping. The median age of women with AGC was 41 years. The outcome was analysed with respect to the median age. In women aged equal or more than 40 years, AGC reflected a high-grade squamous or glandular epithelial abnormality in 50% of cases compared with none in those less than 40 years old ( P  = 0.010).
Conclusion:  The age of the woman as well as the subtype of atypical glandular cells influences outcome and hence must be taken into consideration while formulating an acceptable management strategy in these women in a low-resource setting.  相似文献   
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