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1.
Summary The cytostatic activity of five Bacillus Calmette-Guérin (BCG) strains (Pasteur, Evans, Tice, RIVM and Connaught) on human transitional cell cancer T24 cells was examined. A striking effect was noted even in 2-day cultures, and the effect was more pronounced when the cells were incubated for 5 days with different BCG strains alone. The concentrations needed were about the same as those used in clinical practice (109 colonyforming units of Pasteur strain in 100 ml buffered saline solution). Combination with mitomycin C or interferon--2b potentiated the cytostatic effect. A slight difference in cytostatic activity between different BCG strains was found.  相似文献   
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PURPOSE: We evaluated alternatives to bacillus Calmette-Guerin (BCG) monotherapy using a new combination of chemotherapy and immunotherapy for recurrent superficial bladder carcinoma. MATERIALS AND METHODS: A total of 236 patients with frequently recurrent stage Ta or T1 bladder tumors were enrolled in our prospective, randomized, multicenter Finnbladder IV study. The initial mitomycin C instillation was instilled in all patients perioperatively after transurethral resection, followed by 4 weekly instillations of mitomycin C. Thereafter patients were randomized to receive monthly for up to 1 year BCG only or interferon-alpha2b and BCG alternating monthly. Primary end points were time to initial recurrence, recurrence rate (number of recurrences per patient-year) and recurrence index (number of recurrent tumors per patient-year). RESULTS: Of the 236 randomized patients 205 were eligible for study with a median overall followup of 30.7 months. Monthly BCG was superior to alternating monthly interferon-alpha and/or BCG with respect to time to initial recurrence (log rank test p <0.00001) as well as recurrence rate (0.4 versus 0.9, p <0.00001) and index (0.9 versus 3.0, p <0.00001). Side effects were limited. CONCLUSIONS: Monthly BCG given for up to 1 year preceded by perioperative and an additional 4 weekly mitomycin C instillations is a well tolerated mode of instillation therapy, providing excellent tumor control comparable to that of the best reported instillation regimens. No benefit was obtained by alternating interferon-alpha2b with BCG.  相似文献   
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The discounting of delayed rewards, also known as temporal or delay discounting, is intrinsic to everyday decisions and can be impaired in pathological states such as addiction disorders. Preclinical and human studies suggest a role for dopaminergic function in temporal discounting but this relationship has not yet been verified using molecular imaging of the living human brain. Here, we evaluated dopaminergic function in temporal discounting using positron emission tomography (PET) with two different dopaminergic ligands assessing three populations in whom temporal discounting has been shown to be impaired. First, we show using [11C]raclopride PET that in pathological gamblers, greater temporal discounting correlates with decreased ventral striatal binding potential, convergent with translational findings of lower nucleus accumbens D2/D3 receptor density in high-impulsive rodents. Temporal discounting also correlates with lower ventral striatal dopamine release in response to high-reward magnitude suggesting that dopamine-mediated devaluation of larger delayed rewards may drive choice preferences. Second, we show using [18F]fluorodopa PET that in Parkinson''s disease, temporal discounting correlates with greater left caudate dopaminergic terminal function. Finally, in subjects with Parkinson''s disease and dopamine medication-induced behavioral addictions, temporal discounting is further correlated with greater dopaminergic terminal function in the anterior putamen. These findings provide insights into the relationship between striatal dopamine function and temporal discounting, and its potential role in pathological disorders and mechanisms underlying treatment interventions.  相似文献   
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OBJECTIVES: To study the factors determining new recurrences in patients with frequently recurring superficial bladder tumors. METHODS: Of all 205 eligible patients, each received 5 weekly intravesical instillations of mitomycin C (MMC), with the first instillation given perioperatively. This was followed, according to randomization, by BCG instillations alone or by alternating instillations of interferon-alpha and BCG monthly for up to 1 year. Impact of 12 variables on time to first recurrence was retrospectively studied with the Cox multiple hazards regression and Kaplan-Meier analysis. RESULTS: Type of regimen was the most significant factor determining new recurrences, with preceding recurrence rate being the most important prognostic factor. Timing of the first MMC was the third significant predictor in the main multivariate analysis, with more than a two-fold relative risk for a new recurrence if the first MMC instillation was given later than on day 0. CONCLUSION: Preceding recurrence rate, most accurately reflects, in patients with frequently recurring tumors, the inherent risk for new recurrences. This risk can be considerably reduced by use of an effective chemoimmunotherapy regimen, and in addition, by inclusion of an early perioperative chemotherapy instillation in such a regimen.  相似文献   
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Donepezil and rivastigmine are acetylcholinesterase (AChE) inhibitors used to improve cholinergic neurotransmission and cognitive function in Alzheimer's disease (AD). This study examined direct effects of these drugs on AChE activity in the frontal, temporal, and parietal cortices in AD. Six AD patients were scanned with positron emission tomography before and after 3 months of treatment with donepezil (10 mg/day), and five AD patients were scanned before and after 3 to 5 months of treatment with rivastigmine (9 mg/day). Healthy unmedicated controls were imaged twice to evaluate the reproducibility of the method. A specific AChE tracer, [methyl-11C]N-methyl-piperidyl-4-acetate, and a 3D positron emission tomography system with MRI coregistration were used for imaging. Treatment with donepezil reduced the AChE activity (k3 values) in the AD brain by 39% in the frontal (p < 0.001, Bonferroni corrected), 29% in the temporal (p = 0.02, corrected) and 28% in the parietal cortex (p = 0.05, corrected). The corresponding levels of inhibition for rivastigmine were 37% (p = 0.003, corrected), 28% (p = 0.03, uncorrected) and 28% (p = 0.05, corrected). When the treatment groups were combined, the level of AChE inhibition was significantly greater in the frontal cortex compared to the temporal cortex (p = 0.03, corrected). The test-retest analysis with healthy subjects indicated good reproducibility for the method, with a nonsignificant 0% to 7% intrasubject variability between scans. The present study provides first evidence for the effect of rivastigmine on cortical AChE activity. Our results indicate that the pooled effects of donepezil and rivastigmine on brain AChE are greater in the frontal cortex compared to the temporal cortex in AD. This regional difference is probably related to the prominent temporoparietal reduction of AChE in AD. We hypothesize that the clinical improvement in behavioral and attentional symptoms of AD due to AChE inhibitors is associated with the frontal AChE inhibition.  相似文献   
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OBJECTIVES: Urine cytology is the gold standard in the diagnosis and follow-up of bladder cancer. Cytology, however, exhibits variable sensitivity depending on tumour grade and interpretation of urine specimens is highly dependent on the skill of the examiner. Positive cytology, classes IV and V by Papanicolaou classification, is a strong predictor for coexisting or subsequent malignancy, while the role of suspicious cytology, class III, is controversial. The objective of the study was to evaluate the role of the suspicious finding in cytological analysis, and whether it should be considered as a negative or positive sign for coexisting malignancy. MATERIAL AND METHODS: Six hundred and fifty-two consecutive patients with bladder cancer were studied in a prospective multicenter trial. One hundred and fifty-one of the patients were newly diagnosed, and the remaining 501 patients were under follow-up. A voided urine sample was obtained prior to TURB or prior to routine follow-up cystoscopy in those under the surveillance and split for culture and cytology. The cytopathological results were analyzed by a central review and only patients with samples available for review analysis were included. Sensitivity and specificity, as well as positive (PPV) and negative (NPV) predictive values of urine cytology were calculated by classifying the class III samples as negative or positive. RESULTS: A total of 570 patients were evaluable. One hundred and twenty nine (22.6%) were newly diagnosed and 441 were under follow-up, of whom 117 (26.5%) had recurrence. Cytology was classified as suspicious in 33/129 (25.6%) patients with primary tumour, and in 41/441 (9.3%) of those under the follow-up, of whom 20 (48.8%) had recurrence. Sensitivity increased from to 31.0% to 56.6% in primary tumours (p < 0.001) and from 17.8% to 34.7% in recurrent tumours (p < 0.001) if class III was determined as positive, whereas the specificity decreased from 96.6% to 90.1% (p < 0.001). Accordingly, the NPV increased from 76.3% to 79.1% and the PPV decreased from 65.6% to 56.2%. CONCLUSIONS: The poor sensitivity of voided urine cytology improved significantly when suspicious samples were determined as positive while the specificity remained high, a clear advantage compared with most of the new tumour marker tests. In addition, nearly half of the follow-up patients with suspicious class III cytology had recurrence implying that this patient category is at substantial risk for co-existing malignancy. Therefore, it is recommended that suspicious class III cytology together with class IV and V specimens should be considered positive.  相似文献   
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To study neural correlates of category-specific processing, we measured relative cerebral blood flow changes by PET (oxygen-15) in young healthy subjects while they produced exemplars of animals or artefacts to written subcategory prompts. In comparison to a baseline (word reading), production of animal names elicited increased rCBF in the right inferior temporal region. This fits to recent lesion data on semantic impairment with animals, as well as imaging data on object recognition and semantic retrieval. In our study, it may represent an involvement of visual imagery in generation of animal names. In contrast, production of artefact names elicited increased rCBF in frontoparietal regions previously related to attention and mental effort.  相似文献   
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