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51.
目的分离鉴定蘡Ao地上部分的化学成分。方法通过硅胶柱色谱,Sephadex LH-20及制备HPLC方法分离,对其进行理化常数和光谱分析确定结构。结果自蘡Ao地上部分分离得到11个多酚化合物,均属首次分离。结论化合物1为新化合物,经鉴定其结构为3,5-二甲氧基-4-羟基苯丙醇-9-氧-β-D-吡喃葡萄糖苷。 相似文献
52.
Hideo Yamane Takayuki Nakagawa Hiroyoshi Iguchi Shigetarou Shibata Masahiro Takayama Kishiko Sunami Yoshiaki Nakai 《Auris, nasus, larynx》1997,24(3):221-225
We performed an in vitro study in order to determine possible triggers of hair cell regeneration in the chick basilar papilla following degeneration. We compared the response of sensory epithelium damaged by collagenase treatment with that damaged by acoustic trauma. The former exhibited no proliferative activity, but the latter did. The basilar papillae damaged by acoustic trauma could have proliferating activity in medium containing fetal bovine serum (FBS) or epidermal growth factor (EGF) but not in the medium without FBS or EGF. These findings indicate that regeneration of basilar papillae depends on the manner of cell death and that FBS or EGF is required for regeneration. 相似文献
53.
We constructed a question and answer system for direct delivery of E-mail queries from the general public to the proper hospital representative and with which the system administrator can monitor E-mail replies. The system consists of two sub-systems; one is an E-mail questionnaire sub-system that automatically delivers E-mail queries to the proper person and an E-mail reply monitor sub-system with which the system administrator can monitor the E-mail replies. The monitor system compares the origin address of the E-mail reply and the destination address on a questionnaire filled out at the time the query is made. In a test of the system, 56 queries were received in 31 days, with 37 replied to. The interval from receipt of an E-mail query to reply was calculated. Nineteen replies were submitted within 2 days. 相似文献
54.
55.
Hashimoto T Goto K Hishinuma Y Yachuda K Sugioka Y Arai K Harada S Goto M 《Annals of nuclear medicine》2000,14(4):293-298
99mTc-tetrofosmin, Thallium-201-chloride (201Tl) and 99mTc-MIBI imagings were performed in a patient with malignant thymoma. Tracer uptake in the primary tumor was demonstrated. The tumor-to-background ratios of planar and SPECT imagings were 1.60 and 1.98 for 99mTc-tetrofosmin, 1.12 and 2.09 for 201Tl, and 1.19 and 1.80 for 99mTc-MIBI, respectively. In another patient 99mTc-tetrofosmin and 201Tl imagings were performed. Not only the primary tumor but also the direct invasions and metastatic lesions (bone metastases) were clearly detected. The tumor-to-background ratios of planar and SPECT imagings were 2.31 and 2.78 for 99mTc-tetrofosmin and 2.45 and 3.58 for 201Tl, respectively. In 99mTc-tetrofosmin scintigraphy we acquired delayed images, and the tumor-to-background ratios of planar and SPECT delayed images were 1.20 and 1.86, the retention ratios were -1.11 and -0.92 and the retention indices were -48.1 and -33.1, respectively. Our preliminary results suggest that 99mTc-tetrofosmin is useful in detecting not only the primary tumor but also metastatic lesions from malignant thymoma. 相似文献
56.
Yoshiaki Ikuta Tetsuya Nakatsura Toshiro Kageshita Satoshi Fukushima Shosuke Ito Kazumasa Wakamatsu Hideo Baba Yasuharu Nishimura 《Clinical cancer research》2005,11(22):8079-8088
PURPOSE: There are no available tumor markers detecting primary melanoma at an early stage. The identification of such serum markers would be of significant benefit for an early diagnosis of melanoma. We recently identified glypican-3 (GPC3) as a novel tumor marker but could diagnose only 40% of melanomas. Thereby, we focused out attention on secreted protein acidic and rich in cysteine (SPARC) overexpressed in melanoma as another candidate for tumor marker. EXPERIMENTAL DESIGN: Secreted SPARC protein was quantified using ELISA in the sera from 109 melanoma patients, five patients with large congenital melanocytic nevus, 61 age-matched healthy donors, and 13 disease-free patients after undergoing a surgical removal. We also quantified GPC3 and 5-S-cysteinyldopa in the same serum samples and compared these markers for their diagnostic value. RESULTS: The serum SPARC concentrations in melanoma patients were greater than those in healthy donors (P = 0.001). When we fixed a cutoff value at the mean concentration plus 2 SD of the healthy donors, the serum SPARC was found to have increased in the sera of 36 of the 109 (33%) melanoma patients, whereas there were three (4.9%) false-positive cases of 61 healthy donors. Surprisingly, 19 of 36 patients showing increased SPARC levels were in stages 0 to II. The serum SPARC level decreased under the cutoff level in 10 of 13 patients after surgical removal. Using SPARC and GPC3 in combination thus enabled us to diagnose 47 of 75 (66.2%) melanoma patients at an early stage (0-II). CONCLUSIONS: SPARC or its combination with GPC3 is thus considered a potentially useful tumor marker, especially for melanoma at an early stage. 相似文献
57.
Pradipta Mukherjee Shinichi Fukuda Donny Lukmanto Toshiharu Yamashita Kosuke Okada Shuichi Makita Ibrahim Abd El-Sadek Arata Miyazawa Lida Zhu Rion Morishita Antonia Lichtenegger Tetsuro Oshika Yoshiaki Yasuno 《Biomedical optics express》2022,13(7):4071
Label-free metabolic imaging of non-alcoholic fatty liver disease (NAFLD) mouse liver is demonstrated ex vivo by dynamic optical coherence tomography (OCT). The NAFLD mouse is a methionine choline-deficient (MCD)-diet model, and two mice fed the MCD diet for 1 and 2 weeks are involved in addition to a normal-diet mouse. The dynamic OCT is based on repeating raster scan and logarithmic intensity variance (LIV) analysis that enables volumetric metabolic imaging with a standard-speed (50,000 A-lines/s) OCT system. Metabolic domains associated with lipid droplet accumulation and inflammation are clearly visualized three-dimensionally. Particularly, the normal-diet liver exhibits highly metabolic vessel-like structures of peri-vascular hepatic zones. The 1-week MCD-diet liver shows ring-shaped highly metabolic structures formed with lipid droplets. The 2-week MCD-diet liver exhibits fragmented vessel-like structures associated with inflammation. These results imply that volumetric LIV imaging is useful for visualizing and assessing NAFLD abnormalities. 相似文献
58.
Shigeharu Ohyu Mitsuhiro Tozaki Michiro Sasaki Hisae Chiba Qilin Xiao Yasuko Fujisawa Yoshiaki Sagara 《Magnetic resonance in medical sciences》2022,21(3):485
Purpose: We evaluated the diagnostic performance of the texture features of dynamic contrast-enhanced (DCE) MRI for breast cancer diagnosis in which the discriminator was optimized, so that the specificity was maximized via the restriction of the negative predictive value (NPV) to greater than 98%.Methods: Histologically proven benign and malignant mass lesions of DCE MRI were enrolled retrospectively. Training and testing sets consist of 166 masses (49 benign, 117 malignant) and 50 masses (15 benign, 35 malignant), respectively. Lesions were classified via MRI review by a radiologist into 4 shape types: smooth (S-type, 34 masses in training set and 8 masses in testing set), irregular without rim-enhancement (I-type, 60 in training and 14 in testing), irregular with rim-enhancement (R-type, 56 in training and 22 in testing), and spicula (16 in training and 6 in testing). Spicula were immediately classified as malignant. For the remaining masses, 298 texture features were calculated using a parametric map of DCE MRI in 3D mass regions. Masses were classified into malignant or benign using two thresholds on a feature pair. On the training set, several feature pairs and their thresholds were selected and optimized for each mass shape type to maximize specificity with the restriction of NPV > 98%. NPV and specificity were computed using the testing set by comparison with histopathologic results and averaged on the selected feature pairs.Results: In the training set, 27, 12, and 15 texture feature pairs are selected for S-type, I-type, and R-type masses, respectively, and thresholds are determined. In the testing set, average NPV and specificity using the selected texture features were 99.0% and 45.2%, respectively, compared to the NPV (85.7%) and specificity (40.0%) in visually assessed MRI category-based diagnosis.Conclusion: We, therefore, suggest that the NPV of our texture-based features method described performs similarly to or greater than the NPV of the MRI category-based diagnosis. 相似文献
59.
Nishi T Nawa Y Ueda T Masuda K Taketani F Hara Y 《Journal of cataract and refractive surgery》2006,32(10):1643-1649
PURPOSE: To analyze the effect of total higher-order aberrations (HOAs) on the range of accommodation in pseudophakic eyes and the size of near-vision optotypes. SETTING: Department of Ophthalmology, Nara Medical University, Nara, Japan. METHODS: The study comprised 30 patients (44 eyes) who were diagnosed with cataract at Nara University of Medical Science Hospital and Municipal Oyodo Hospital. Inclusion criteria included no other eye disorder and a best corrected distance acuity of 20/20 or better 1 month after cataract surgery. All patients had small-incision phacoemulsification followed by in-the-bag implantation of a monofocal intraocular lens (SA60AT, Alcon). All incisions were self-sealing. Accommodation in pseudophakic eyes was measured by the lens-loading method in an examination room under constant illumination. Ocular HOAs were measured using the KR-9000PW Hartmann-Shack wavefront analyzer (Topcon). RESULTS: The mean patient age was 75.8 years +/- 5.4 (SD) (range 64 to 83 years). The Pearson correlation coefficient (r) showed a significant positive correlation between the range of accommodation and Z7 (vertical coma) for a 4.0 mm pupil using the 1.0 near-vision optotype. There was a significant negative correlation between the range of accommodation and Z12 (spherical aberration) for a 4.0 mm pupil using the 1.0 near-vision optotype (r = .311, P = .040 for Z7;r = -.365, P = .015 for Z12). No other parameter was significantly correlated with the range of accommodation. CONCLUSIONS: Measurement of accommodation in pseudophakic eyes by the lens-loading method using the 1.0 near-vision optotype showed that eyes with larger vertical coma aberrations achieved a larger range of accommodation. In contrast, eyes with larger spherical aberrations had smaller amounts of accommodation. The size of the near-vision optotype may affect accommodation analysis in pseudophakic eyes. 相似文献
60.
Yiling Wu Hiroaki Saito Akihiko Ozaki Tetsuya Tanimoto Yonggen Jiang Peng Yang Jing Li Zhiming Zhou Xiuguo Zhu Fei Lu Yoshiaki Kanemoto Tomohiro Kurokawa Masaharu Tsubokura Genming Zhao 《Medicine》2022,101(32)
Little is known about the participation rate of newly implemented colorectal cancer (CRC) screening programs in China. Our goals were to identify factors associated with nonparticipation for CRC screening in Songjiang District, Shanghai.We analyzed individuals included in an observational cohort study from 4 towns (Xin Qiao, She Shan, Mao Gang, and Zhong Shan) in Songjiang District. The participation rate was calculated for the CRC screening program based on a fecal immunochemical test and a risk assessment questionnaire between 2015 and 2017 inclusive.Of the 27,130 individuals eligible for inclusion in this study, 20,863 (76.9%) participated in CRC screening at least once during 2015 and 2017. The factors linked with nonparticipation were; being male (odds ratio [OR] 0.87, 95% confidence interval [CI] 0.82–0.93, P < .01), unmarried (OR 0.71, 95% CI 0.64–0.80, P < .01), having a high education level (middle school, OR 0.82, 95% CI 0.74–0.90, P < .01, high school or above, OR 0.64, 95% CI 0.57–0.73, P < .01), absence of chronic disease (OR 0.90, 95% CI 0.85–0.96, P < .01), and living in 2 out of the 4 towns covered (Xin Qiao, OR 0.72, 95% CI 0.66–0.78, P < .01, Zhong Shan, OR 0.29, 95% CI 0.26–0.31, P < .01).The current study revealed several associated factors with nonparticipation for the CRC screening in Songjiang district. These findings will help identify target populations that require an individualized approach to increase the participation rate. 相似文献