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排序方式: 共有1795条查询结果,搜索用时 31 毫秒
91.
Eri Arai Saori Ushijima Hitoshi Tsuda Hiroyuki Fujimoto Fumie Hosoda Tatsuhiro Shibata Tadashi Kondo Issei Imoto Johji Inazawa Setsuo Hirohashi Yae Kanai 《Clinical cancer research》2008,14(17):5531-5539
PURPOSE: The aim of this study was to clarify genetic and epigenetic alterations occurring during renal carcinogenesis. EXPERIMENTAL DESIGN: Copy number alterations were examined by array-based comparative genomic hybridization analysis using an array harboring 4,361 bacterial artificial chromosome clones, and DNA methylation alterations on CpG islands of the p16, human MutL homologue 1, von Hippel-Lindau, and thrombospondin 1 genes and the methylated in tumor (MINT-1, MINT-2, MINT-12, MINT-25, and MINT-31) clones were examined in 51 clear cell renal cell carcinomas (RCC). RESULTS: By unsupervised hierarchical clustering analysis based on copy number alterations, clear cell RCCs were clustered into the two subclasses, clusters A (n=34) and B (n=17). Copy number alterations were accumulated in cluster B. Loss of chromosome 3p and gain of 5q and 7 were frequent in both clusters A and B, whereas loss of 1p, 4, 9, 13q, and 14q was frequent only in cluster B. The average number of methylated CpG islands in cluster B was significantly higher than those in cluster A. Clear cell RCCs showing higher histologic grades, vascular involvement, renal vein tumor thrombi, and higher pathologic stages were accumulated in cluster B. The recurrence-free and overall survival rates of patients in cluster B were significantly lower than those of patients in cluster A. Multivariate analysis revealed that genetic clustering was a predictor of recurrence-free survival and was independent of histologic grade and pathologic stage. CONCLUSIONS: This genetic clustering of clear cell RCC is significantly associated with regional DNA hypermethylation and may become a prognostic indicator for patients with RCC. 相似文献
92.
Yasushi Naito Eri Naito Iwao Honjo Anita Newman Vicente Honrubia 《Hearing research》1995,90(1-2):72-78
Cytochrome oxidase (CO) activity of the vestibular ganglion cells of the squirrel monkey was demonstrated histochemically under normal and experimental conditions. Under general anesthesia, right vestibular nerve section was performed on adult squirrel monkeys between the vestibular ganglion and brain stem. The left side was left intact and was used as a within-animal normal control. One squirrel monkey that did not undergo vestibular nerve section was also included in the normal group. Following a survival period of seven months, neurons in the vestibular ganglion of both sides were examined. In the normal control sides, a significant negative correlation between the size of the neuron and its optical density for CO stain was observed. Many neurons in the vestibular ganglion survived after vestibular nerve section, but their cell sizes and optical densities of CO stain decreased compared with those of the control side. 相似文献
93.
Cyclosporin A(CyA) is used frequently in the treatment of steroid-resistant or recurrent cases with nephrotic syndrome. Recently, a new microemulsion formulation of CyA(Neoral) has been developed and used preferably because of a more stable bioavailability than an oily formulation(Sandimmun). Nephrotic syndrome accompanies hyperlipidemia, and probucol is used in cases showing inadequate effects or some adverse reactions under therapy with HMG-CoA reductase inhibitors. We reported previously that combined use of probucol caused a decrease in blood concentrations of CyA to about half of those without probucol. In the present study, we evaluated the influence of probucol on the blood concentrations of CyA in patients with nephrotic syndrome following Neoral. Coadministration of Neoral and probucol decreased the blood concentrations of CyA to approximately 75% of the levels before combined use. The change of blood CyA concentrations appeared to be smaller compared to those in cases with Sandimmun. Based on the present findings, we suggest that Neoral should be used preferentially instead of Sandimmun when the concomitant use of probucol is required, and that optimal dose adjustment of CyA is needed by frequent monitoring of CyA blood concentrations. 相似文献
94.
Effect of Perilla frutescens on nitric oxide production and DNA synthesis in cultured murine vascular smooth muscle cells 总被引:1,自引:0,他引:1
The effects of perilla (Perilla frutescens, Labiatae) on murine cultured vascular smooth muscle cells (VSMC) were investigated. The water extract of perilla leaves induced nitric oxide (NO) production of VSMC and this effect was synergistically augmented when combined with interferon (IFN)-gamma or tumour necrosis factor (TNF)-alpha, while the perilla extract significantly inhibited NO production induced by IFN-gamma combined with lipopolysaccharide (LPS). Northern blot analysis revealed that these effects of the perilla extract paralleled mRNA expression of inducible nitric oxide synthase. However, the perilla extract significantly inhibited platelet derived growth factor (PDGF) or TNF-alpha-induced VSMC proliferation measured as DNA synthesis. The inhibitory effect of the perilla extract on TNF-alpha-induced VSMC proliferation was significantly suppressed by N(G)-monomethyl-L-arginine, a non-specific nitric synthase inhibitor, suggesting that this effect was partially mediated by NO production as an autocrine/paracrine factor. The present findings suggest that perilla would be useful for the prevention of vascular diseases such as arteriosclerosis. 相似文献
95.
PURPOSE: The purpose of this study was to evaluate the extent of pseudoenhancement in a phantom model using three different CT scanners. METHODS: The phantom consisted of a water-filled balloon (cyst) suspended in varying concentrations of iodine solution, meant to simulate varying levels of renal enhancement. The phantom was scanned with single detector-row CT scanners of three different manufacturers. All scans were performed at 120 kV and 200 mA with 5 mm collimation. RESULTS: The degree of pseudoenhancement differed among the three scanners. In two of the scanners, the attenuation of water in the balloon (cyst) was noted to increase significantly as the iodine concentration in the cylinder was increased. However, the degree of pseudoenhancement was different between the two scanners. In the other scanner, attenuation of the cyst was noted to decrease as the iodine concentration in the cylinder decreased and to increase as the iodine concentration in the cylinder increased. CONCLUSION: The degree of pseudoenhancement may vary in scanners of different manufacturers. We may need to check the pattern and degree of pseudoenhancement in CT scanners before determining the enhancement threshold for simple renal cyst. 相似文献
96.
We evaluated six alternative methods of prostate volume determination by transrectal ultrasound, three based on planimetry and three based on measurement of prostate diameters. Prostate volume measurements were made on an average of 6.5 occasions over a 3 y period on 41 patients with benign prostatic hyperplasia, using standard techniques. We defined the average of multiple planimetries as the prostate reference volume. Agreement with the reference volume and reproducibility at repeat testing was in the same range for single planimetry and volume determinations based on the formulas height (H) x width (W) x length (L) x pi/6 and W x W x H x pi/6, but was poorer using the formula W x W x W x pi/6. Using the average result of two successive planimetry measurements increased the reproducibility of planimetry, being statistically significantly better than for one single planimetry (P=0.024) or for the formula W x W x H x pi/6 (P=0.048). Our study suggests that the simple formula based methods of prostate volume determination provide results that are only marginally inferior to one single planimetry, but results are improved by performing two planimetry measurements. 相似文献
97.
CT demonstration of dilated gonadal vein as a portosystemic shunt of mesenteric varices 总被引:2,自引:0,他引:2
Gokan T Kushihashi T Nobusawa H Hashimoto T Matsui S Kitanosono T Munechika H 《Journal of computer assisted tomography》2001,25(5):798-801
PURPOSE: The purpose of this work was to assess CT demonstration of the enlarged gonadal vein as a portosystemic shunt of mesenteric varices. METHOD: The clinical records and CT images of eight patients with angiographically confirmed mesenteric varices were studied retrospectively. We measured the size of the right gonadal vein of these eight patients and also measured the size of the right gonadal vein in 60 patients without mesenteric varices. RESULTS: In all eight patients, CT demonstrated that the mesenteric varices drained into the inferior vena cava through the dilated right gonadal vein (diameter 6-10 mm) in all and that the left gonadal vein was not dilated (diameter 2-3 mm). In 60 patients without mesenteric varices, the diameter of the right gonadal vein was 1-5 mm. CONCLUSION: CT demonstrates the dilated gonadal vein as a portosystemic shunt of the mesenteric varices. Awareness of a dilated gonadal vein in patients with portal hypertension may be helpful to consider the possibility of mesenteric varices. 相似文献
98.
Nakazawa Y Matsubara Y Suzuki M Asako E Honda A 《Gan to kagaku ryoho. Cancer & chemotherapy》2005,32(Z1):24-26
The appearance of vasculitis is often observed following the use of epirubicin hydrochloride in outpatients. As it is important to continue to provide a safe treatment for outpatient with little or no side effects, the aim of this study was to reveal causes underlying the outbreak of vasculitis or the vasculitic state of patients who had undergone instillation of epirubicin hydrochloride as an adjuvant therapy following a breast cancer surgery. The study was conducted based on past investigation records. We extracted relevant factors such as age, previous illness, physical condition and dosage of epirubicin hydrochloride from past records which may all be connected to the outbreak of vasculitis. We administered one dose of epirubicin hydrochloride that was diluted into 50-100 ml of normal saline solution or 5% glucose and instilled over a period of 30 minutes. As a result of this instillation of epirubicin hydrochloride, 35 out of 45 cases displayed vasculitis. We did not observe any relationship among the aged (over 60), previous illness or physical condition (BMI over 25) and the appearance of vasculitis. When a dosage amount of more than 110 mg of epirubicin hydrochloride was administered, 23 out of 29 cases displayed vasculitis. From the past records, it was observed that the cause of vasculitis was dependent on the administrative method itself. As previous studies reported that vasculitis was low when epirubicin hydrochloride was retained in blood vessels for only a short time, our study, however, concentrated on how to administer epirubicin hydrochloride. Our results suggested that an adoption of a single dosage system may suppress the outbreak of vasculitis. 相似文献
99.
Muramatsu T Mukai M Sato S Tajima T Nagase E Ikeda M Goya K Shida M Hirasawa T Murakami M Shinozuka T 《Oncology reports》2005,14(4):861-865
We compared the preoperative serum tumor marker values and diameters of ovarian tumors between 14 stage Ia ovarian cancer patients with a good prognosis and 14 stage Ic patients with a poor prognosis. The aim was to examine the usability of tumor markers and diameter of ovarian tumors for prognostic diagnosis of clinically advanced phases. In occult neoplastic cells (ONCs), a tumor marker indicative of recurrence and metastasis, the cytokeratin-positive cells in lymph node biopsies, were also compared. In a preoperative comparison of serum tumor markers, CA125 levels in stage Ia and Ic patients were 47.1+/-15.9 (median, 31.9 U/ml) and 370.6+/-146.2 U/ml (median, 135.6 U/ml), respectively (p=0.0457), and CA19-9 levels were 25.5+/-5.5 (median, 20.4 U/ml) and 564.5+/-192.4 U/ml (median, 248.0 U/ml), respectively (p=0.0131). In a comparison of tumor diameters during surgery, diameters of stage Ia and Ic patients were 117.3+/-11.4 (median, 100.0 mm) and 182.0+/-29.2 mm (median, 145.0 mm), respectively (p=0.0457). ONCs were not detected in any stage Ia patients, but detected in 3 (30%) stage Ic patients. In conclusion, clinical progression was evaluated using CA125 and CA19-9 serum markers and tumor diameters in stage Ia and Ic patients, and demonstrated significant differences between stage. ONCs were only detected in the lymph nodes of stage Ic patients. 相似文献
100.
Nakao K Tsunoda A Shimizu Y Takenaka K Morohara K Suzuki N Yamazaki K Aoki T Hoshino M Kusano M Kitadai E Kurihara T Takeuchi Y Imawari M 《International journal of clinical oncology / Japan Society of Clinical Oncology》2005,10(4):281-284
In a 64-year-old man who had been treated with prednisolone (PSL) and 6-mercaptopurine (6MP) for a long period, for ulcerative colitis (UC), hepatocellular carcinoma (HCC) was detected incidentally. The UC was in remission with these medications. After he had been taking these medications for about 8 years, HCC was detected by computed tomography (CT), done for the evaluation of an other disease. Blood chemistry examination results were normal, except that the protein induced by vitamin K antagonist (PIVKA)-II level was 7940 AU/ml. We performed resection of liver segment V. With comparative genomic hybridization, chromosomal aberrations were recognized; these were gains of 1q, 3ptel-21, 8p12, and 22q11.23–22q13.1. Generally, HCC is associated with hepatitis virus infection in most cases, but in this patient, the HCC was not related to hepatitis C virus (HCV) or HBV. It is presumed that this case was related to the immunosuppressive therapy for UC and was associated with the gains of 1q, 3p, and 8p. 相似文献