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991.
To distinguish hepatocellular carcinoma (HCC) from normal liver tissue, a color map was made by dynamic contrast-enhanced 256-detector row CT developed at our institute. Dynamic enhanced CT of the liver of three patients with HCC was studied. The CT has 912 (transverse) x 256 (cranio-caudal) elements, each measuring approximately 0.5 mm x 0.5mm at the center of rotation. Scanning for 10 s (1.0 s/rotation) was started 30 s after intravenous injection of contrast medium. The reconstruction increment was 0.62 mm with a time interval of 0.1s and a matrix size of 512 x 512 x 256. Color maps were generated to show the gradient of the regression line of the time-density change. Due to volume acquisition, the 3D color map can be created using continuous 10-s scanning. The densities of the HCC and liver were decreased and increased during scanning, respectively. The HCC was detected clearly in the color map as a downward-sloping region. Dynamic enhanced 256-detector row CT could be useful for detecting malignant tumors in the liver with a short scan time.  相似文献   
992.
OBJECTIVE: The relationships among regional diastolic impairment, the elongation of global time to peak filling rate (g-TPF), and global diastolic function were examined by a novel program using electrocardiography-gated myocardial perfusion single-photon emission computed tomography (SPECT) (GMPS) in heart failure (HF). METHODS: Fifteen control subjects and 70 HF patients, New York Heart Association functional classification I (N-1) 41 cases, classification II (N-II) 15 cases, and classification III (N-III) 14 cases, were examined by GMPS. Using the reference mean +2 SD (standard deviation) of g-TPF derived from control group (CG), HF patients were divided into a normal g-TPF group (NG) and elongated g-TPF group (EG). The distributions of g-TPF and regional (r-) TPF were estimated by histograms. The extension of regional diastolic impairment was estimated by the number of r-TPF elongated segments (NES). RESULTS: g-TPF and r-TPF mainly distributed from 100 ms to 220 ms and demonstrated a peak around 150 ms in CG and NG. g-TPF distributed from 240 ms to 560 ms, but r-TPF distributed from 90 ms to 690 ms and demonstrated two peaks around 150 ms and 350 ms in EG. NES significantly correlated with g-TPF (r=0.79, P=6x10(-10) in N-I; r=0.69 and P<0.005 in N-II; r=0.89, P=2x10(-5) in N-III). NES negatively correlated with first third filling fraction (1/3FF) (r=-0.83, P=3x10(-11) in N-I; r=-0.72, P<0.0005 in N-II) and first third filling rate (1/3FR) (r=-0.49, P=0.002 in N-I; r=-0.52, P=0.002 in N-II; r=-0.81, P<0.0005 in N-III). g-TPF significantly correlated with 1/3FF (r=-0.67, P=1.5x10(-6) in N-I; r=-0.69, P<0.005 in N-II) and 1/3FR (r=-0.41, P<0.01 in N-I; r=-0.69, P<0.01 in N-III). CONCLUSIONS: The development of regional early diastolic impairment makes g-TPF elongation and induces global dysfunction in early diastole.  相似文献   
993.
BACKGROUND: Immunohistochemically detectable isolated tumour clusters (ITCs) with a diameter of less than 0.2 mm have been regarded as non-metastatic lesions, because of a lack of proliferative activity. This study investigated the proliferative activities of ITCs. METHODS: Three hundred and eight patients with primary gastric cancer diagnosed as pN0 by routine histological examination were studied. All patients underwent curative resection. Sections of lymph nodes were stained by double-immunostaining methods using anti-cytokeratin and anti-Ki-67 antibody (MIB-1). RESULTS: ITCs were detected in 77 nodes from 37 patients, designated as having pN0(i+) lesions. Seventy of 77 lymph nodes with ITCs were detected in the N1 station, and seven were found in the N2 station. Of 25 single isolated cancer cells, 12 showed positive labelling with MIB-1, and 49 of 52 ITCs with clusters of cancer cells had positive MIB-1 labelling (mean(s.d.) 46.6(30.1) per cent). Five of the 37 patients with ITCs (pN0(i+)) versus one of the 271 patients with no evidence of ITCs (pN0(i-)) died from recurrence. Patients with ITCs had a significantly worse prognosis than those without (P = 0.014). CONCLUSION: ITCs have a high proliferative activity and may have the potential to evolve into established lymph node metastasis.  相似文献   
994.
995.
Elevated production of cysteinyl leukotrienes (cysLTs) from sinus tissues and abundant sinus eosinophils are characteristic features of chronic hyperplastic eosinophilic sinusitis (CHS). CysLTs exert their action through G-protein-coupled receptors named cysLTs receptor type I (cysLT1R) and type II (cysLT2R). These expressions of cysLT receptors in the sinus mucosa have yet to be clarified and the relationship between eosinophilia and the expression of these receptors remains obscure. We compared the expressions of cysLT1R and cysLT2R in the sinus mucosa in patients with CHS, non-eosinophilic chronic sinusitis (NECS), and control sinus tissues; and analyzed the correlation between the expression of CysLTRs and the presence of sinus eosinophils by immunohistochemistry and real-time PCR. A significantly higher percentage of eosinophils expressing cysLT2R protein was observed in patients with CHS compared with NECS and controls. In addition, cysLT2R mRNA expression in CHS was significantly higher than in NECS and controls. Furthermore, a positive correlation was observed between cysLT2R mRNA expression and the number of infiltrated eosinophils. In contrast, the cysLT1R mRNA expression did not differ significantly among these groups. The effect of cysLTs on sinus eosinophils may be mediated through the cysLT2R in patients with CHS. These results may suggest the therapeutic benefit of cysLT2R antagonists in CHS.  相似文献   
996.
IgG4-related disease has been recently described. This disease occurs in various anatomic locations including pancreas, biliary tract, liver, retroperitoneum, kidney, breast, lung, thyroid gland, prostate, salivary gland, lacrimal gland, and lymph node. In this article, we report the first case of IgG4-related disease arising in the renal pelvis. A 49-year-old Japanese woman was found to show left hydronephrosis by a medical checkup. Histological examination of the renal pelvic tumor showed IgG4-related disease. Her postoperative serum IgG4 was elevated, and this was compatible with IgG4-related disease. Systemic examination showed swelling of major and minor salivary glands and the lacrimal glands, and biopsy of the minor salivary gland revealed the finding of IgG4-related disease. Finally, pathologists and clinicians should be aware of the possibility that the renal pelvis may be involved in IgG4-related systemic disease.  相似文献   
997.
998.
A 66-year-old man with a 39-year history of anal fistula was admitted to our hospital for anal pain and bleeding. Fistulectomy was carried out for anal fistula. Histological examination of the specimen revealed carcinoma associated with anal fistula. A computed tomography showed that the tumor had invaded the prostate. Therefore, preoperative chemoradiotherapy(S-1 plus radiation 40 Gy/body)for locally advanced cancer was performed. Magnetic resonance imaging showed that the boundary between the tumor and the prostate was unclear, but we performed an abdominoperineal resection and the prostate was fully preserved. Histopathologically, no cancer cell existed on the surgical margin. The histological effect of chemoradiotherapy was judged as grade 2. This case suggested that surgical treatment combined with preoperative chemoradiotherapy may be effective for locally advanced carcinoma associated with anal fistula, in which preservation of adjacent organs is considered to be difficult.  相似文献   
999.
1000.
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