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31.
Carcinoma of the oral cavity constitutes approximately 40% of overall malignant tumours in India, with an incidence of about 56,000 cases per year. Radiation responses in oral cancer cells by cytology have not been extensively studied. 102 patients with squamous cell carcinoma of the oral cavity treated by fractionated radiotherapy were studied. Serial scrape smears were taken from each tumour before and after irradiation. The abnormal nuclear counts per 1000 malignant cells were 1.6 and 14.1(p<0.001) for micronucleation, 0.9 and 5.5 (p<0.001) for nuclear budding, 7.6 and 28.1(p<0.001) for binucleation and 2.4 and 11.7(p<0.001) for multinucleation respectively. The study showed a significant rise in radiation induced cytological responses. In addition, radiation changes observed included abnormal and incomplete divisions of a nucleus, fibroblast like appearance cells, and enlargement of nuclear size as well as cytoplasmic granulation. These changes may have an important role to play in understanding the mechanism of cell killing after radiotherapy. 相似文献
32.
Unsharp masking is a widely used image-enhancement method in medical imaging. Hardware-based solutions can be developed to support high computational demand for unsharp masking, but they suffer from limited flexibility. Software solutions can easily incorporate new features and modify key parameters, such as filtering kernel size, but they have not been able to meet the fast computing requirement. Modern programmable mediaprocessors can meet both fast computing and flexibility requirements, which will benefit medical image computing. In this article, we present fast adaptive unsharp masking on two leading mediaprocessors or high-end digital signal processors, Hitachi/Equator Technologies MAP-CA and Texas Instruments TMS320C64x. For a 2k × 2k 16-bit image, our adaptive unsharp masking with a 201 × 201 boxcar kernel takes 225 ms on a 300-MHz MAP-CA and 74 ms on a 600-MHz TMS320C64x. This fast unsharp masking enables technologists and/or physicians to adjust parameters interactively for optimal quality assurance and image viewing. 相似文献
33.
Standardization for image characteristics in telemammography using genetic and nonlinear algorithms 总被引:2,自引:0,他引:2
As the soft copy reading and computer assisted diagnosis (CAD) in mammography become more and more important, the standardization of digital images becomes paramount. Telemammography and telemedicine requires the standardization for image characteristics, such as image resolution, bit-depth and intensity response. Soft copy reading and CAD in mammography are both dependent on the characteristics of the source of the digital data, either direct digital mammography or digitized screen-film mammography. An algorithm developed on images from one database may not perform well as on images from another database (with a different digitization). In this paper, we describe two methods based on a genetic algorithm and a nonlinear algorithm for standardization of digitized and digital mammography. The proposed standardization techniques are based on geometric and intensity transformations that are discovered using a set of calibration images. A set of transformation algorithm is used to search for the best standardization. 相似文献
34.
Mehrotra R 《Indian journal of pathology & microbiology》2004,47(3):377-380
Fine needle aspiration cytology has become the first choice in diagnostic procedures in the management of a variety of breast diseases. The technique can be successfully used to diagnose granuloma in breast aspirates and to demonstrate the presence of acid-fast bacilli. Tuberculosis is rampant in developing countries and patients are prescribed antituberculous therapy on the basis of finding granuloma in breast aspirates without a culture report. In our practice, this principle has been followed with excellent results. In our experience, this technique was reliable and reproducible in diagnosing tuberculous mastitis. We report on the cytomorphological findings of this uncommon but important disorder. 相似文献
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A comparative study of perinatal mortality patterns over a period was conducted at a teaching hospital of South India. Among
the 6,048 babies born from January 1984 to December 1985 (Group A), there were 265 (43.8/1000) still births and 127 (22.0/1000)
early neonatal deaths. Three hundred and thirty seven (41/1000) babies were still born and 235 (29.8/1000) early neonatal
deaths out of 8,215 deliveries during 1992–93 (Group B). The perinatal mortality rate (PMR) in Group A and B were 57.9/1000
and 57.7/1000 respectively. Unbooked cases accounted for the majority (> 75%) of perinatal deaths during both the periods.
The overall mortality rates in unbooked cases were three to four times higher than booked cases. Among the various causes
of still births, antepartum haemorrhage and uterine rupture had increased. Septicaemia was the major cause of early neonatal
deaths in Group A, but in Group B birth asphyxia and prematurity were the leading causes. Effective interventions like creating
awareness among the target population to utilise maternal and child health services and early referral of high risk cases
with improved intranatal and perinatal care can decrease the perinatal mortality. 相似文献
39.
Of the 397 patients undergoing total laryngectomy for squamous cell carcinoma by Professor P. M. Stell between 1963 and 1991, 73 are known to have suffered a local recurrence. Of these, 17 were treated by radiotherapy and/or further surgery. Secondary surgery was reserved for selected cases of peristomal and pharyngeal recurrence: of the 35 peristomal recurrences, eight were treated surgically. Previous reports of recurrence after total laryngectomy have focused on the problem of peristomal recurrence. Patients with pharyngeal recurrences can also be treated satisfactorily with microvascular surgical reconstruction techniques. Though rarely curative, secondary total pharyngectomy can be highly palliative and results in little additional morbidity. 相似文献
40.
Ravi Ramalingam K. K. Ramalingairr A. V. Ramesh S. Mahesh Prabhu Manu Vergis N. Ahilasamy 《Indian journal of otolaryngology and head and neck surgery》2003,55(4):294-295
The incidence of Papillary Thyroid Carcinoma in a Thyroglossal Cyst is rare. Only about 160 cases have been reported in the
last 85 years. We report a case of Thyroglossal Cyst who underwent Sistrunk ’s Operation. The Cyst was reported to
contain a focus of papillary thyroid carcinoma. In the absence of metastases in thyroid gland and neck nodes, only thyroid
suppression with Thyroxine was given. After I year of follow-up there are no metastases. The importance of Sistrunk’s
operation lies not only in complete removal of Thyroglossal Cyst but also in management of small foci of Papillary thyroid
Carcinoma. 相似文献