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91.
92.
Background The purpose of this study was to assess the accuracy of contrast-enhanced magnetic resonance imaging (dynamic MR imaging) in the evaluation of preinvasive and early invasive cancer of the cervix. Methods Twenty-nine women with untreated squamous cell carcinoma of the cervix with either no stromal invasion or early stromal invasion underwent pretreatment MR imaging and dynamic MR imaging within 4 weeks of surgical evaluation. The images were evaluated for tumor detection and compared with results of histologic examination of the surgical specimens. Results The lesions in 17 cases with histologically proven stromal invasion of 4 mm or greater were detected with dynamic MR imaging, whereas lesions in only 8 of these cases were detected with T2 imaging. In 9 cases with stromal invasion between 4.0 mm and 5.0 mm, lesions were represented as early phase focal enhancement on dynamic MR images, but not detected on T2-weighted images. In the 12 cases with less than 4 mm stromal invasion, no lesions were visualized on either T2-weighted images or dynamic MR images, except in 1 case of glandular involvement without stromal invasion that appeared as enhancement on early-phase dynamic MR imaging. Conclusion Dynamic MR imaging detected more lesions of early stromal invasion in pretreatment imaging for cervical cancer than nonenhanced MR imaging.  相似文献   
93.
Although maladaptive coping strategies in eating disorder patients have been reported, the relationship between impulsivity and coping strategy has not previously been studied. Subjects consisted of 43 patients with anorexia nervosa restricting type (AN-R), 42 patients with anorexia nervosa binge eating/purging type (AN-BP), 71 patients with bulimia nervosa purging type (BN), and 97 controls. The Coping Inventory for Stressful Situations was used to evaluate coping strategies. Only AN-BP patients had a significantly lower task oriented-coping score than controls, and AN-R and BN patient groups used significantly less social diversion-avoidance coping strategies than controls. Emotion-oriented coping scores of AN-BP and BN patients were significantly higher than those of controls. In addition, impulsive BN patients had significantly higher emotional coping scores than less impulsive BN patients. These results suggest that maladaptive coping strategies may be a perpetuating factor even for impulsive patients and emphasizing a change in maladaptive coping strategies may be a useful treatment strategy even for highly impulsive patients.  相似文献   
94.
A 59-year-old man was transferred to our hospital because of severe right leg pain, dyspnea and anuria. Due to severe cyanosis of the legs below the knees and severe hyperkalemia, he had undergone embolectomy of the right femoral artery and hemodialysis. Medical treatment for infective endocarditis was started after the first operation, because transesophageal echo cardiography revealed severe aortic regurgitation and massive vegetation of the aortic valve. Amputation of the right leg below the knee and of the left leg below the Lisfranc joint was performed after 19 days and aortic valve replacement with patch closure of a perivalvular abscess was performed one month after the first operation. The post-operative course was uneventful. He was weaned from hemodialysis and the follow-up echocardiographic study revealed no vegetation.  相似文献   
95.
Oligodendrocytes are myelin forming cells in mammalian central nervous system. About 50% of oligodendrocytes (OLGs) undergo cell death in normal development. In addition, OLG cell deaths have been observed in demyelinating diseases including multiple sclerosis (MS). Clinical observations and in vitro cell culture studies have suggested that cytokines mediate OLG cell damage in multiple sclerosis (MS). Among the cytokines, tumor necrosis factor (TNF) is thought to be one of the mediators responsible for the damage of OLGs in MS. The administration of TNF-alpha to primary cultures of OLGs induced DNA fragmentation, and significantly decreased the number of live OLGs. Chemical inhibitors Ac-YVAD-CHO (a specific inhibitor of caspase-1 (ICE)-like proteases) enhanced the survival of TNF-alpha treated OLGs better than Ac-DEVD-CHO (a specific inhibitor of caspase-3 (CPP32)-like proteases). These results indicate that caspase-1-mediated cell-death pathway are activated in TNF-induced OLG cell death. Caspase-11 is involved in activation of caspase-1. Oligodendrocytes from caspase-11-deficient mice are partially resistant to TNF-induced OLG cell death. Our results suggest that the inhibition of caspase-1 sufamily may be a novel therapeutic approach to treat MS.  相似文献   
96.
BACKGROUND: Recent laboratory studies have suggested that cadmium is an estrogenic compound and may be a potential risk factor for breast cancer. METHODS: We investigated the relationship between urinary cadmium concentrations and serum concentrations of estrone, testosterone, and dehydroepiandrosterone sulfate in 164 postmenopausal Japanese women. RESULTS: There was a significant positive association between the urinary cadmium and serum testosterone levels after controlling for age and body mass index. The mean testosterone level was 28% higher in women with high urinary cadmium (> or = 3.00 microg/g creatinine) than in those with low urinary cadmium (< 2.00 microg/g creatinine). Urinary cadmium was not significantly associated with serum estrone and dehydroepiandrosterone sulfate levels. Additional adjustment for smoking, alcohol and reproductive factors including known risk factors for breast cancer did not substantially alter the results. CONCLUSION: Data suggested that cadmium exposure is associated with increased testosterone levels. As high testosterone levels have been associated with the risk of breast cancer, the involvement of cadmium exposure in breast cancer risk should be evaluated in future studies.  相似文献   
97.
Imexon is an aziridine-containing small molecule currently in Phase I clinical trials. This agent has been shown to bind to thiols and increase intracellular oxidants, inducing apoptosis in hematologic cancer cells. Pancreatic cancers are known to be sensitive to oxidation, suggesting this disease may be an appropriate target for this agent. The current report examines the activity of imexon in pancreatic cells. Imexon induced concentration-dependent and time-dependent apoptosis in a panel of six human pancreatic carcinoma cell (PCC) lines. The mean IC50 (SD) for growth inhibition by the SRB assay was 200 (101) µM for a 48 h exposure with a range of 64–358 µM. Cell killing was schedule-dependent, favoring exposure times ≥48 h. Imexon-treated MiaPaCa-2 cells underwent non-lethal growth arrest following exposure to concentrations ≤200 µM for 48 h. When concentrations were increased to 300 µM for ≥48 h, the MiaPaCa-2 cells arrested in G2 phase and activated caspases 3, 8, and 9 were detected. After a 72 h exposure to the IC80 concentration of imexon, cells exhibited a loss of mitochondrial membrane potential detected by CMXRos staining. However, there was no loss of reduced cellular thiols unless very high concentrations of ≥400 µM were used. In contrast, reactive oxygen species (ROS) were elevated in a dose-dependent fashion, starting at very low imexon concentrations. Imexon also significantly inhibited MiaPaCa-2 tumor growth in SCID mice at 100 mg/kg/d for 9 d. The tumor growth inhibition (% T/C) was 27% of control, and the tumor growth delay was 21 d, indicating an active agent by NCI standards. The levels of imexon that are cytotoxic in human PCC’s are achievable based on the preliminary results of the ongoing Phase I trial. Imexon appears to be active against PCCs in vitro and has an entirely novel mechanism of action involving G2 arrest, accumulation of ROS, and the induction of apoptosis.  相似文献   
98.
99.
Cholecystokinin 2 (CCK2) receptors have been implicated as mediators of anxiety in standard mouse models such as exploratory behavior both in black and white test boxes and in elevated plus-mazes. We investigated the role of the CCK2 receptor in anxiety by evaluating the behavior of mice lacking the gene for this receptor in these standard anxiety models (i.e., exploratory behavior in a black and white test box and exploratory behavior in an elevated plus-maze). In the black and white test box, mice lacking the CCK2 receptor gene showed significantly increased numbers of transitions between the boxes compared to control mice. In the elevated plus-maze, mice lacking the CCK2 receptor gene displayed significantly more head dips than control mice. These results suggest that mice lacking the CCK2 receptor gene are less anxious than normal mice.  相似文献   
100.
Lipid peroxidation and oxidative stress may play a certain role in the pathogenesis of pressure-induced atherosclerosis, and alcohol related diseases. Recently, 8-isoprostane in biological fluids has been reported to be a reliable marker for lipid peroxidation and oxidative stress in vivo. In the present study, we developed an ELISA method for 8-isoprostane which has high sensitivity, intra- and inter-assay reproducibility and wide dynamic assay range. Using this method, we examined the effects of drinking and smoking habits on plasma levels of 8-isoprostane in healthy subjects. A total of 157 apparently healthy volunteers was assayed for plasma 8-isoprostane. Subjects were divided into three groups according to their alcohol consumption. Group I is non- or few-drinkers, Group II includes subjects who drink once or twice a week, and subjects of Group III intake 3 to 5 times a week or almost every day. In addition, the same population was divided into two groups, 96 non-smokers and 61 smokers. Plasma 8-isoprostane was extracted with ODS gel followed by NH2 Sep-Pak column. The 8-isoprostane fractions thus separated were assayed by a commercial ELISA kit (Cayman Chemical). The plasma 8-isoprostane was estimated to be 20.9 +/- 93 pg/ml in a total of 157 volunteers (83 male, 74 female). The plasma 8-isoprostane levels were elevated in the Group III (26.6 +/- 9.5 pg/ml) compared with Group I (20.3 +/- 6.1 pg/mL, p<0.0001) and Group II (20.9 +/- 5.7 pg/ml, p<0.001). Significant increase of the plasma 8-isoprostane was observed only in habitual drinkers of females, but not in those of males. On the other hand, no significant difference of the plasma 8-isoprostane levels were observed between non-smokers (21.5 +/- 7.3 pg/ml) and smokers (22.8 +/- 7.4 pg/ml, p>0.05). We suppose that plasma 8-isoprostane may increase in the habitual drinkers due to the oxidization stress induced by alcohol intake, and it may become a useful marker to estimate drinking habit  相似文献   
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