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101.
102.
Detection studies of simulated low-contrast radiographic patterns were performed with a high-quality digital image processing system. The original images, prepared with conventional screen-film systems, were processed digitally to enhance contrast by a "windowing" technique. The detectability of simulated patterns was quantified in terms of the results of observer performance experiments by using the multiple-alternative forced-choice method. The processed images demonstrated a significant increase in observer detection performance over that for the original images. These results are related to the displayed and perceived signal-to-noise ratios derived from signal detection theory. The improvement in detectability is ascribed to a reduction in the relative magnitude of the human observer's "internal" noise after image processing. The measured dependence of threshold signal contrast on object size and noise level is accounted for by a statistical decision theory model that includes internal noise. 相似文献
103.
Neves Lia Mara Grosso Tim Carla Roberta Floriano Elaine Medeiros da Silva de Avó Lucimar Retto Fernandes João Batista Parizotto Nivaldo Antonio Cominetti Marcia Regina 《Lasers in medical science》2021,36(4):863-870
Lasers in Medical Science - Ultraviolet radiation (UVR) is the major etiologic agent of cutaneous photoaging, and different strategies are used to prevent and treat this condition. The... 相似文献
104.
105.
Kenichiro Ishida Yusuke Katayama Tetsuhisa Kitamura Tomoya Hirose Shunichiro Nakao Jotaro Tachino Yutaka Umemura Takeyuki Kiguchi Tasuku Matsuyama Kosuke Kiyohara Takeshi Shimazu Mitsuo Ohnishi 《Journal of pediatric surgery》2021,56(5):1013-1019
PurposeThe aim of this study was to assess the association between the implementation of abdominal angiography and outcome among pediatric patients with blunt splenic or hepatic injury.MethodsThis was a retrospective observational study, with a study period of 14 years, from January 2004 to December 2017. Blunt-trauma patients with splenic or hepatic injury who were less than 19 years old were included in this study. We used propensity-score-(PS) matching analysis to assess the relationship between abdominal angiography and in-hospital mortality.ResultsIn total, 639 patients were eligible for analysis, with 257 patients included in the abdominal-angiography group and 382 patients in the no-abdominal-angiography group. After PS matching, 224 patients from each group were selected. In the PS matched patients, in-hospital mortality was lower in the abdominal-angiography group than in the no-abdominal-angiography group (4.9% vs. 11.2%, odds ratio 0.416, 95% confidence interval 0.177–0.903).ConclusionIn this population, the implementation of abdominal angiography was significantly associated with lower in-hospital mortality among pediatric patients with blunt splenic or hepatic injury compared with nonimplementation of abdominal angiography.Type of studyPrognosis study.Level of evidenceIII 相似文献
106.
Ishihara Hiroki Fukuda Hironori Tachibana Hidekazu Yoshida Kazuhiko Kobayashi Hirohito Takagi Toshio Iizuka Junpei Ishida Hideki Nagashima Yoji Kondo Tsunenori Tanabe Kazunari 《Clinical and experimental nephrology》2021,25(6):674-682
Clinical and Experimental Nephrology - The data regarding oncological outcome in advanced renal cell carcinoma (RCC) arising in end-stage renal disease (ESRD) are limited. Patients diagnosed with... 相似文献
107.
Photoreceptor differentiation of retinoblastoma: An electron microscopic study of 29 retinoblastomas
Yasuo Tajima Shigeru Munakata Yasuo Ishida Tohru Nakajima Isamu Sugano Koichi Nagao Kensei Minoda Yoichiro Kondo 《Pathology international》1994,44(12):837-843
Retinoblastomas exhibit a unique form of differentiation to produce cell elements similar to those seen in a photoreceptor cell. An ultrastructural study was performed on 29 cases of retinoblastoma to further clarify the cytologic characteristics of the tumor cells. The age of the retinoblastomas averaged 17.1 months and the tumor cells showing photo-receptor differentiation were demonstrated in 10 cases (35%). The findings were especially notable in retinoblastomas with Flexner-Wintersteiner rosette formation (seven cases, 28%). Similar photoreceptor differentiation was also evident in solid cell clusters without rosette formation (four cases, 14%). The presence of photoreceptor elements was assumed to be significantly frequent both in Flexner-Wintersteiner rosettes and in the solid cell clusters. The cell cytoplasm also showed proliferation of long mitochondria and microtubules, reflecting photoreceptor differentiation. The hereditary-type retinoblastoma showed more advanced cell differentiation than the non-hereditary type. Photoreceptor differentiated retinoblastoma showed rather indolent growth compared with the undifferentiated type, and the former can expect a curative treatment by operation. These observations provide additional findings of the biological nature of retinoblastomas. 相似文献
108.
K Yoshida R Abe S Itoh T Taguchi J Ohta T Morimoto T Ishida H Tashiro M Ogita C Kido 《Japanese journal of clinical oncology》1990,20(4):374-379
In a nation-wide collaborative study on mass screening for breast cancer, we collected 152 cases of interval breast cancer diagnosed at 35 hospitals or clinics distributed throughout Japan. The definition of interval breast cancer used in the present study is "breast cancer cases which were diagnosed as having 'no malignant findings' in a previous screening for breast cancer but subsequently diagnosed as 'breast cancer' at a hospital or medical clinic within two years of the previous screening." The clinical stages and prognoses of these interval cancer were analyzed and compared with those of other breast cancers detected through mass screening and in outpatient clinics. In the clinical staging of interval breast cancer, Tis (non infiltrating cancer) accounted for only 2.1%, compared to 8.0% in cases detected through mass screening. At stage I 43.4% were interval breast cancers compared to 32.9% breast cancers detected through mass screening and 25.4% diagnosed in outpatient clinics. The stage differences between interval breast cancers and breast cancers detected through mass screening were not statistically significant. Five-year survival rates were 85.6% for interval breast cancers, 91.7% for breast cancers detected through mass screening and 84.7% for breast cancers diagnosed in outpatient clinics. Ten-year survival rates were 75.9, 80.5 and 78.1%, respectively, suggesting the interval breast cancer cases to show a similar prognosis to that of breast cancer cases diagnosed in outpatient clinics. The differences in five- and 10-year survival rates among the three groups were not statistically significant. From the present study we were not able to confirm the general belief of interval cancer being more aggressive in nature and showing a poorer prognosis than cancer detected through periodic screening. The reasons for this are discussed. 相似文献
109.
We have developed a breast-conserving surgery consisting of quadrantectomy and regional lymph node dissection and immediate
volume replacement using lateral tissue flap (LTF). The quadrantectomy was employed on the basis of segmental anatomy of the
duct lobular system in which breast carcinoma originates. Lateral skin incision was performed from the apex of mid-axillary
line to the inframammary fold, without removing the skin overlying the tumor. In the early period of breast reconstruction
embraced latissmus dorsi flap (LDF) for 10 patients (reconstruction was not performed on 35 patients), but in the late period
we employed LTF for 56 patients. Four of the 101 patients developed ipsilateral breast cancer during a mean follow-up period
of 48 months, but none died of breast cancer. Among the 56 patients with LTF replacement no patient developed ipsilateral
breast cancer. Fairly good cosmetic outcome was obtained in the patients who underwent the immediate volume replacement. Breast-conserving
surgeries are reviewed, and the surgical procedure using LTF for immediate volume replacement is described. 相似文献
110.