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31.
Continuous wave near-infrared spectroscopy (NIRS) measurements of cardiac correlated changes in attenuation in the adult human head were computed using a Fourier analysis technique that eliminates the positive error bias associated with the magnitude of the Fourier coefficient. These attenuation changes were used to determine wavelength dependence of differential pathlength, DP(lambda), at four stages during progressive hypoxia (21, 17, 13 and 9% FIO2) in normal volunteers. The effects of incorporating DP(lambda) into NIRS algorithms to compute relative concentration changes and absolute concentration of oxyhaemoglobin and deoxyhaemoglobin are discussed. Because variations in DP(lambda) are restricted to wavelengths below 780 nm, absolute concentration calculations are influenced by hypoxia-induced changes while relative concentrations are unaffected. However, even accounting for changes in DP(lambda) did not allow computation of physiologically reasonable absolute concentrations of the haemoglobin species. 相似文献
32.
The mutational spectrum of brachydactyly type C 总被引:3,自引:0,他引:3
Everman DB Bartels CF Yang Y Yanamandra N Goodman FR Mendoza-Londono JR Savarirayan R White SM Graham JM Gale RP Svarch E Newman WG Kleckers AR Francomano CA Govindaiah V Singh L Morrison S Thomas JT Warman ML 《American journal of medical genetics》2002,112(3):291-296
Growth/differentiation factor-5 (GDF5), also known as cartilage-derived morphogenetic protein-1 (CDMP-1), is a secreted signaling molecule that participates in skeletal morphogenesis. Heterozygous mutations in GDF5, which maps to human chromosome 20, occur in individuals with autosomal dominant brachydactyly type C (BDC). Here we show that BDC is locus homogeneous by reporting a GDF5 frameshift mutation segregating with the phenotype in a family whose trait was initially thought to map to human chromosome 12. We also describe heterozygous mutations in nine additional probands/families with BDC and show nonpenetrance in a mutation carrier. Finally, we show that mutant GDF5 polypeptides containing missense mutations in their active domains do not efficiently form disulfide-linked dimers when expressed in vitro. These data support the hypothesis that BDC results from functional haploinsufficiency for GDF5. 相似文献
33.
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
34.
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
35.
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
36.
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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Eden-Hybinette Procedure for Revision Surgery in Recurrent Anterior Shoulder Instability in Epilepsy
AimsThe purpose of this study was to analyze the clinical outcomes after Eden-Hybinette procedure for revision surgery in recurrent anterior shoulder instability in patients with epilepsy.Materials and MethodsWe retrospectively evaluated eight such patients between 2015 and 2018. Four patients had failed Latarjet/Bristow procedure and two had failed arthroscopic Bankart procedure, while two had history of both the procedures. After medical control of epilepsy, Eden-Hybinette procedure was performed in all patients. WOSI score and Rowe shoulder score was recorded preoperatively and in subsequent post-operative follow-up. A paired t test was used to analyze and compare preoperative and postoperative outcomes and was considered significant if p value was < 0.05.ResultsThe average follow-up was 30 months (range 24–48 months). There was no recurrence of shoulder instability. The mean WOSI score before surgery was 77.3 (range 70–83), which improved to 24.2 (range 19–30) at 24-month follow-up. The mean Rowe score before surgery was 11.3 (range 5–15), which improved to 81.8(range 65–90) at 24-month follow-up. The improvement in WOSI and Rowe score was found to be statistically significant [p value < 0.05]ConclusionsWe conclude that Eden-Hybinette is a useful revision procedure to manage recurrent anterior shoulder dislocation in patients with epilepsy. Optimum medical control of seizure is also an important factor in preventing recurrent shoulder instability 相似文献