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21.
Background: There have been a few evidence‐based studies concerning the relationship between the length of the surveillance interval of colonoscopic examinations and the risk of colorectal cancer (CRC). The aim of the present study was to assess the appropriate interval between endoscopic examinations for CRC screening in a retrospective cohort study. Methods: The cohort included subjects in whom cancer was not detected at the initial endoscopic examination and in whom endoscopic examination(s) was subsequently performed one or more times. The results of the endoscopic examinations performed in the mass screening for CRC between November 1983 and March 1999 were analyzed. The study end point was the detection of CRC and the detection rates of cancer were assessed among those who underwent examinations at various intervals between successive endoscopic examinations. Results: Among the 117 636 cohort subjects, 63 invasive cancer cases and 112 mucosal cancer cases were found. The odds ratio (OR) for invasive cancer was not significantly elevated even when the interval between successive examinations was over 5 years. The OR for mucosal or invasive cancer was significantly elevated among the subjects in whom the interval between successive examinations was over 5 years (OR, 1.71; 95% confidence interval (CI), 1.07–2.73), than among those in whom the interval was 1 year. Conclusions: Since prolongation of the interval between endoscopic examinations of up to 5 years did not result in any change in the cancer risk among persons who are at average risk for CRC, 5 years may be an adequate interval between endoscopic examinations in the mass screening for CRC.  相似文献   
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It has been reported that aggressive immunosuppressive treatment is effective for controlling the disease activity of refractory systemic lupus erythematosus (SLE). However, little information on a regimen including tacrolimus (TL) for the treatment of refractory SLE has been available. We report a successful low dose TL treatment of a 25-year-old male patient with refractory SLE. He developed SLE with proliferative lupus nephritis(WHO class IVb) at the age of 11 years. During the past 4 years, despite aggressive immunosuppressive treatment consisting of methylprednisolone pulse therapy, mizoribine pulse therapy, cyclosporine A and intravenous cyclophosphamide pulse therapy, frequent flares associated with presumptive hypercytokinemia i.e., increased levels in the serum C-reactive protein, ferritin and soluble IL-2 receptor, occurred. Hence, administration of low-dose TL at 3 mg per day, was initiated. The blood levels of TL at approximately 12 hours post-dosing were maintained at between 3 and 5 ng/mL. Within 3 weeks following TL administration, the serum levels of C3, C4 and CH50 began to increase rapidly, and the prednisolone dose could be successfully tapered. No adverse effects of TL were observed. We suggest that TL may be the treatment of choice for selected patients with refractory SLE.  相似文献   
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The diagnostic value of computed tomography (CT) scans in small hepatocellular carcinoma (HCC) (less than 5 cm) was studied in 82 patients. Dynamic scan was also made in 66 of them. Combined unenhanced and enhanced scans detected 87% of the lesions greater than 2 cm, but the detection rate was only 25% for lesions less than 1.5 cm. Diagnostic failure was due to isodensity of the mass and to technical artefacts. Diagnosis of the surrounding capsule and internal septa (partition) and demonstration of the typical pattern of density enhancement by dynamic scan proved useful in differentiating HCC from secondary cancers. On unenhanced CT, the density of the interior was subject to the histological changes of tumour such as bleeding, necrosis and fatty metamorphosis. Similarly, enhanced CT showed density changes suggestive of these histological changes. Dynamic scan proved particularly useful for lesions less than 3 cm because the typical density enhancement was frequently demonstrated in the arterial phase. It was concluded that unenhanced CT combined with dynamic scan has a high diagnostic value in small HCC and reflects histological changes.  相似文献   
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Tarsal tunnel syndrome (TTS) is a common entrapment syndrome whose diagnosis can be difficult. We compared preoperative magnetic resonance imaging (MRI) and operative findings in 23 consecutive TTS patients (28 sides) whose mean age was 74.5 years. The 1.5T MRI sequence was 3D T2* fat suppression. We compared the MRI findings with surgical records and intraoperative videos to evaluate them. MRI- and surgical findings revealed that a ganglion was involved on one side (3.6%), and the other 27 sides were diagnosed with idiopathic TTS. MRI visualized the nerve compression point on 23 sides (82.1%) but failed to reveal details required for surgical planning. During surgery of the other five sides (17.9%), three involved varices, and on one side each, there was connective tissue entrapment or nerve compression due to small vascular branch strangulation. MRI studies were useful for nerve compression due to a mass lesion or idiopathic factors. Although MRI revealed the compression site, it failed to identify the specific involvement of varices and small vessel branches and the presence of connective tissue entrapment.  相似文献   
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Abstract— The vasorelaxant effects of the K+-channel openers, pinacidil and cromakalim, were compared with those of the Ca2+-channel blockers, verapamil and KB-2796 (1-[bis(4-fluorophenyl)methyl]-4-(2,3,4-trimethoxybenzyl)piperazine dihydrochloride), in canine isolated coronary, renal, basilar and mesenteric arteries precontracted with U46619, a thromboxane A2 mimetic. The relaxation induced by pinacidil and cromakalim was greater in coronary than in other arteries, the magnitude of relaxation being in the order of coronary > renal > basilar > mesenteric arteries. The relaxant responses to both drugs were inhibited by glibenclamide, a blocker of ATP-sensitive K+ channels. The relaxation induced by verapamil and KB-2796, in contrast, was greater in basilar than in other arteries, the magnitude of relaxation being in the order of basilar > coronary > renal and mesenteric arteries. In fura-2-loaded, U46619-stimulated arteries, pinacidil and cromakalim produced a greater reduction in intracellular Ca2+ concentration and muscle tension in coronary than in mesenteric arteries, while verapamil and KB-2796 reduced these values more potently in basilar than in mesenteric arteries. These results suggest that K+-channel openers exhibit a vasorelaxant selectivity for coronary arteries, whereas Ca2+-channel blockers exhibit such selectivity for cerebral arteries. The selective vasorelaxant action induced by these drugs appears to correspond, in part, to their effects on the concentration of intracellular Ca2+.  相似文献   
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BACKGROUND: The role of calcitonin gene-related peptide (CGRP) in prostate cancer has not been fully understood. Moreover, the serum CGRP level in prostate cancer patients has never been reported. We measured the serum CGRP levels in untreated prostate cancer patients to elucidate its clinical significance. MATERIALS AND METHODS: We used 36 serum samples from prostate cancer patients. All patients had never received any treatment. Serum CGRP was measured by immunoradiometric assay, and we analysed the association between serum CGRP level and clinicopathological factors. RESULTS: Serum CGRP levels in the patients with higher clinical stages and histological grade were significantly higher than in those with lower stages and grade, respectively. But the levels did not correlate with the patient's age, liver or renal functions, serum prostate-specific antigen levels. CONCLUSION: Serum CGRP levels were significantly elevated in the patients with high grade or high stage untreated prostate cancer patients. Measurement of the serum CGRP may be a useful predictor of staging or grading of prostate cancer in the untreated prostate cancer patients.  相似文献   
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