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61.
Abstract: To determine the role of telomere-mediated gene stability in hepatocarcinogenesis, we examined the telomere length of human liver with or without chronic liver diseases and hepatocellular carcinomas (HCC). The mean telomere restriction fragment (TRF) length of normal liver (n=13), chronic hepatitis (n=11), liver cirrhosis (n=24) and HCC (n=24) was 7.8±0.2, 7.1±0.3, 6.4±0.2 and 5.2±0.2 kb, respectively (mean±standard error). TRF length decreased with a progression of chronic liver diseases and that in HCC was significantly shorter than that in other chronic liver diseases (p<0.05). The ratios of TRF length of HCC to that of corresponding surrounding liver of well differentiated (n=7), moderately differentiated (n=10) and poorly differentiated (n=4) HCCs were 0.83±0.06, 0.75±0.05 and 0.98±0.09, respectively. The ratio of poorly differentiated HCC was significantly higher than that of moderately differentiated HCC (p<0.05). A comparison between the size and telomere length ratio of moderately differentiated HCCs revealed a decrease of the ratio with size until it reached 50 mm in diameter. In contrast, the ratio increased as the size enlarged over 50 mm. These findings suggest that the gene stability of the liver cells mediated by the telomere is reduced as chronic liver disease progresses and that telomerase is activated in poorly differentiated HCC and moderately differentiated HCC over 50 mm in diameter.  相似文献   
62.
Here we report a case that was diagnosed as sarcoidosis but required differential diagnosis from pneumoconiosis. A 51-year-old asymptomatic man, who showed signs of bilateral hilar lymphadenopathy (BHL) on a chest X-ray taken during a medical check, was given a diagnosis of sarcoidosis, based on the results of mediastinoscopic mediastinal lymph node biopsy. Because of the presence of large and small nodular lesions adjacent to the pleura extending from the bilateral upper lobes into the lung field, and continuous bead-like, small nodular lesions in the right interlobar pleura, pleural sarcoidosis was suspected and thoracoscopy was performed. Macroscopically, multiple grayish-white nodules with distinct margins, up to 1cm in diameter surrounded by a proliferation of capillaries were found in the pleura, particularly in the upper lobes. Lesions were also scattered over the interlobar pleura and diaphragmatic surface. Histopathologically, several non-caseous epithelioid cell granulomas and silicotic nodule-like lesions of hyaline degeneration were found; therefore, pneumoconiosis, or more specifically chronic berylliosis, was suspected. Despite these symptoms, the patient did not have a history of exposure, and the results of the lymphocyte stimulation test using beryllium were negative in blood and bronchoalveolar lavage fluid. The patient was given a diagnosis of pleural sarcoidosis and has been observed without treatment.  相似文献   
63.
We attempted to determine the usefulness of body surface mapping (BSM) for differentiating patients with Brugada syndrome (BS) from patients with asymptomatic Brugada syndrome (ABS). Electrocardiograms (ECG) and BSM were recorded in 7 patients with BS and 35 patients with ABS. Following the administration of Ic antiarrhythmic drugs, BSM was recorded in 5 patients with BS and 16 patients with ABS. The maximum amplitudes at J0, J20, J40 and J60 were compared between the 2 groups, as were 3-dimensional maps. The maximum amplitudes at J0, J20 and J60 under control conditions were larger in patients with BS than in patients with ABS (P < 0.05). A three-dimensional map of the ST segments under control conditions in patients with BS showed a higher peak of ST elevation in the median precordium compared to that for patients with ABS. Increases in ST elevation at J20, J40 and J60 following drug administration were greater in patients with BS than in patients with ABS (P < 0.05). Evaluation of the change in amplitude of the ST segment at E5 caused by Ic drug administration was also useful for differentiating between the 2 groups. In conclusion, BSM was useful for differentiating patients with BS from those with ABS.  相似文献   
64.
We isolated and characterized three multidrug-resistant clinical isolates of group B streptococci with reduced penicillin susceptibility (PRGBS) that formed small non-beta-hemolytic colonies on sheep blood agar plates but grew well on chocolate agar plates. They can be overlooked in the bacterial identification step, leading to clinical misdiagnosis and treatment failure.  相似文献   
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66.
The aim of this study is to investigate the expression of three prostaglandin E synthase (PGES) isomers in colorectal cancer (CRC) tissue and to evaluate their relationship to clinicopathological factors and patient prognosis. Microsomal PGES (mPGES)-1, mPGES-2, cytosolic PGES (cPGES) and cyclooxygenase (COX)-2 protein expression were analyzed by real-time polymerase chain reaction and Western blot. The localization of each PGES and COX-2 protein was examined by immunohistochemistry in 155 surgical resections and correlated to clinicopathological factors and patient prognosis. mPGES-1 mRNA and protein levels were significantly higher in CRC than in paired normal tissues. mPGES-1 immunoreactivity localized in cancer cells in 43% of cases. mPGES-2 immunoreactivity was significantly more pronounced in cancer cells than in adjacent normal epithelium in 36% of cases. cPGES immunoreactivity was homogeneous in cancer cells and thus determined constitutive. mPGES-1 and mPGES-2 correlated with significantly worse prognosis in stage I–III patients. These results indicate that mPGES-1 and mPGES-2 may each play a role in CRC progression.  相似文献   
67.
Mucinous cystic neoplasms (MCNs) are generally defined as cyst‐forming epithelial neoplasms that arise in the pancreas and harbor characteristic ovarian‐type stroma beneath the epithelium. In this study, we compared the immunoreactivity of steroid‐related factors in these subepithelial stromal cells in MCNs to those in intraductal papillary mucinous neoplasms (IPMNs) to further characterize this unique MCN ovarian‐type stroma through evaluation of sex steroid biosynthesis. Twenty MCNs and twenty IPMNs were examined. Immunoreactivity of steroid hormone receptors, including estrogen receptor (ERα and ERβ), progesterone receptor (PR, PR‐A, and PR‐B), and androgen receptor (AR), was more frequently detected in MCN ovarian‐type stromal cells than in IPMN stromal cells (P < 0.01). The H‐scores (mean ± SD) of steroidogenic factor (SF)‐1 were also significantly higher in MCNs (112.3 ± 33.1) than in IPMNs (0.9 ± 1.2) (P < 0.01). The steroidogenic enzymes cytochrome P450 cholesterol side‐chain cleavage enzyme (P450scc), cytochrome P450 17 alpha‐hydroxylase (P450c17) and 3β‐hydroxysteroid dehydrogenase (3β‐HSD) showed immunoreactivity in 9/20 (45.0 %), 15/20 (75.0 %) and 13/20 (65.0 %), respectively, of ovarian‐type stroma from MCN cases. These results demonstrate that the ovarian‐type stroma of MCNs can express steroidogenic enzymes. Thus, the ovarian‐type stroma of MCNs can produce sex steroids that may also act on these cells.  相似文献   
68.
69.
The present study investigates whether lymphatic vessel invasion (LVI) detected by D2‐40 staining is a prognostic factor for stage I adenocarcinoma of the lung. We retrospectively reviewed 124 patients who underwent complete resection for stage I adenocarcinoma of the lung from January 1983 to June 2003. LVI was microscopically evaluated using D2‐40 immunostaining. The median follow‐up was 71 months. The LVI positive rate was 37%. The 5‐year cancer‐specific survival rates of the D2‐40 positive LVI and negative groups were 88.8% and 84.3%, respectively (P = 0.630). The stage I lung adenocarcinoma patients who were determined to be LVI positive based on D2‐40 immunostaining did not have a significantly poorer prognosis than the LVI negative cases. Thus, lymphatic microinvasion may not be a prognostic indicator in early lung cancer, although advanced LVI does appear to correlate with survival. It is therefore unnecessary to use D2‐40 immunostaining to diagnose LVI in practical settings, and Hematoxylin‐Eosin and Elastica van Gieson staining should continue to be used to predict the prognosis of patients with stage I lung adenocarcinoma.  相似文献   
70.
Intestinal necrosis associated with cation exchange resin (CER) is considered related to sorbitol, but it has been reported even in patients receiving CER alone. This study was performed to identify the risk factors of CER‐related intestinal necrosis. The pathological database of 61 end‐stage renal disease patients with surgical intervention for intestinal perforation was reviewed. The correlations between CER treatment and clinicopathological factors were studied among three groups: (i) patients administered CER and with CER at the perforation site (n = 23), (ii) patients administered CER with undetected CER at the perforation site (n = 12) and (iii) patients not administered CER (n = 26). The majority of the perforation site in group 1 was in the sigmoid colon (82.6%) with significantly higher average age and more frequent CER adhesion rates to the mucosa around the perforation site than group 2. The laxative administration rate in group 1 was significantly higher than group 3 and tended to be higher than group 2. The incidence of CER‐related intestinal necrosis was estimated at 0.57%. CER should be used with extreme caution in elderly patients with passage disturbance.  相似文献   
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