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471.
Little is known about the effects of recurring depressive episodes on cognition and behavior. The objective of the study was to compare cognitive function and depression-related behavior between healthy female subjects and female outpatients with early-onset DSM-IV recurrent major depressive disorder and to investigate the effect of cumulative depressive duration. Neuropsychological tests and scales for apathy, anhedonia and psychomotor retardation were assessed in 23 female patients and 60 healthy age-matched female controls. Significantly higher levels of apathy, anhedonia and psychomotor retardation, and worse performance on tests of executive function were found in the patient group compared with the healthy controls. In the patient group, cumulative depression duration was not significantly correlated with cognitive function, apathy, anhedonia or psychomotor retardation. The deficits in executive function were not related to the actual level of depression. Mild executive dysfunction may be the effect of the illness process underlying recurrent depressive disorder. Repeated or extensive depressive episodes do not seem to additionally affect cognitive deficits or behavior in depressed patients.  相似文献   
472.
Leukocyte common antigen-related (LAR) protein is a cell adhesion molecule-like receptor-type protein tyrosine phosphatase. We previously reported that in LAR tyrosine phosphatase-deficient (LAR-Delta P) mice the number and size of basal forebrain cholinergic neurons as well as their innervation of the hippocampal area was reduced. With the hippocampus being implicated in behavioural activity aspects, including learning and memory processes, we assessed possible phenotypic consequences of LAR phosphatase deficiency using a battery of rodent behaviour tests. Motor function and co-ordination tests as well as spatial learning ability assays did not reveal any performance differences between wildtype and LAR-Delta P mice. A spatial learning impairment was found in the difficult variant of the Morris water maze. Exploration, nestbuilding and activity tests indicated that LAR-Delta P mice were more active than wildtype littermates. The observed hyperactivity in LAR-Delta P mice could not be explained by altered anxiety or curiosity levels, and was found to be persistent throughout the nocturnal period. In conclusion, behavioural testing of the LAR-Delta P mice revealed a spatial learning impairment and a significant increase in activity.  相似文献   
473.
Aneurysms of the portal venous system are increasingly reported in the past five years. Congenital weakness of the venous wall, trauma, pancreatitis and portal hypertension are possible etiologies. Surgical intervention is indicated in case of symptomatic aneurysms with or without progressive expansion of the aneurysm diameter. The treatment of asymptomatic splenic vein aneurysms remains debated. We report the case of an asymptomatic and uncomplicated splenic vein aneurysm for which a conservative approach was advocated with regular follow-up by means of Doppler ultrasonography. After six years of follow-up the aneurysm diameter has not changed and no complications were observed.  相似文献   
474.
475.
Background: 18-F-fluorodeoxyglucose positron emission tomography (FDG-PET) is valuable in staging of esophageal cancer. However, FDG-PET may falsely upstage patients leading to incorrect exclusion from surgical treatment. This study was performed to determine the false-positive rate and possible causes.Methods: The rate of false-positive lesions on FDG-PET was documented in 86 out of a group of 98 patients. Lesions were defined as false positive when pathological examination was negative or as absence of tumor activity within 6 months of follow-up. To evaluate the influence of a learning curve on the false-positive rate, the PET scans were revised recently.Results: False-positive lesions were found in 13 patients (13 of 86; 15%). FDG-PET incorrectly revealed only locoregional node metastases in 5 patients in whom surgery with curative intent was performed. Ten lesions in the other 8 patients were classified as distant organ or as nonregional node metastases (M1a/1b). Finally, 5 patients upstaged to M1a/1b underwent a curative resection. The number of false-positive lesions decreased from 16 to 5 (6%) after revision.Conclusions: Proper interpretation of FDG-PET in staging esophageal cancer is impeded by false-positive results. Even after completion of the learning curve, positive FDG-PET findings still have to be confirmed by additional investigations.  相似文献   
476.
Radio-frequency ablation (RFA) is used as a minimally invasive treatment for inoperable hepatic tumors. Immunological reactions secondary to RFA may play a role in the observed tumor control. In our study, the VX2 carcinoma was implanted into the liver of rabbits. After 3 weeks, tumors were treated with RFA or were left untreated. Peripheral blood lymphocytes were harvested before tumor implantation, 2 weeks postoperatively and at 2-week intervals thereafter. T cells were stimulated with lysates of either tumor tissue or nontumorous liver loaded on autologous antigen-presenting cells and their stimulation index was determined by [(3)H]thymidine incorporation. A 3-fold increase over background or controls was considered significant. Stimulation with phytohemagglutinin served as a positive control. The animals were necropsied, and liver and tumor tissue were analyzed immunohistologically for T-cell infiltration. T cells from tumor-bearing (n = 9) and RFA-treated (n = 11) animals were investigated in a follow-up study. The mean postoperative observation was 45 days. All of the 11 RFA-treated animals exhibited circulating T cells activated specifically toward tumor antigens throughout the observation period, which was accompanied by dense T-cell infiltration. In contrast, T cells of untreated tumor-bearing rabbits showed no reaction and only sparse T cell infiltration. We concluded that RFA induces a tumor-specific T-cell reaction in the otherwise unreactive tumor-bearing host, apparently overcoming immune tolerance and leading to the presentation of otherwise cryptic tumor antigens. Therefore, in addition to destroying tumor tissue, RFA induces an immune response against tumor antigens that may be exploited in multimodal antitumor strategies.  相似文献   
477.
Flexible Sigmoidoscopy for Colorectal Cancer Screening in the Elderly   总被引:2,自引:0,他引:2  
Data on performance characteristics of flexible sigmoidoscopy (FS) between age groups are limited. This study evaluates screening FS in subjects > or = 75 years of age (elderly) compared with ages 50-74 years (general screening population). Data were collected on patient characteristics, insertion depth, procedural difficulties, complications, and endoscopic findings. There was an increased rate of endoscopist-reported limitations (50.4% vs. 34.9%; P = 0.0001) and incomplete examinations (15.6% vs. 5.4%; P = 0.0001) in the elderly cohort relative to subjects aged 50-74. The complication rate (1.0% vs. 1.5%; P = 0.53), adenoma detection rate (7.2% vs. 5.6%; P = 0.213), and advanced adenoma detection rate (0.71% vs 0.65%; P = 0.86) were similar. More carcinomas were detected in the elderly (0.53% vs. 0.06%; P = 0.042). Factors associated with incomplete examinations in the elderly included age, female gender, and poor bowel preparation. Despite technical difficulties, FS in the elderly is safe and detects significant pathology.  相似文献   
478.
BACKGROUND: Internal medicine residents are deficient in their knowledge about familial colorectal cancer (CRC) and thus unable to comply with appropriate screening guidelines. The objective of this study was to evaluate the effectiveness of a mixed educational program that incorporates both a didactic lecture (DL) and interactive, case-based seminar (ICBS), plus distribution of a personal digital assistant (PDA)-based risk assessment tool. METHODS: Internal medicine resident continuity care teams were randomly assigned to an intervention (9 teams; 43 residents) or control (11 teams; 39 residents) arm. Both groups participated in a DL addressing the current status of CRC screening for average, moderate, and high-risk groups. Intervention teams also participated in a 1-h pre-clinic ICBS that included vignettes about patients at moderate or high risk of CRC because of family history, following which they received the risk assessment tool by e-mail. Knowledge and clinical risk assessment skills were evaluated using pre/posttests, patient exit interviews, and chart audits. RESULTS: Baseline test scores were similar for both groups (intervention, 51%vs control, 54%; p= 0.35). Immediate post-ICBS scores (intervention group only) significantly increased to 82% (p < 0.001). Six-month post-ICBS scores declined for the intervention group but remained significantly higher than 6-month control group scores (63%vs 56%, p= 0.002), which were unchanged from baseline. No significant differences were observed with respect to family history-taking or documentation skills. CONCLUSION: A mixed educational program that incorporates both a DL and ICBS is more effective that the DL alone for increasing knowledge about familial CRC risk but may have limited influence on clinical risk assessment skills.  相似文献   
479.
GOALS: Our primary objectives were to assess knowledge about familial risk and risk communication among colorectal adenoma patients. BACKGROUND: The first-degree relatives (FDRs) of colorectal adenoma patients diagnosed before the age of 60 years may be at increased risk of colorectal cancer and should begin screening by the age of 40 years. Adherence to this recommendation requires effective risk communication between physicians, affected patients, and their at-risk relatives. STUDY: We conducted a telephone survey of 129 consecutive English-speaking adenoma patients younger than 60 years treated by 11 endoscopists at two medical centers. Information regarding patient demographics, awareness of familial risk, and risk communication was elicited. RESULTS: A total of 71 eligible subjects responded to the survey. Few responders (n = 25, 33%) were aware that their FDRs were at increased risk of colorectal cancer, and only 56% of knowledgeable patients identified a physician as the source of information. Awareness was strongly associated (P < or = 0.001) with patient-initiated information-seeking behavior. Most knowledgeable patients (n = 20, 80%) reported that they had informed > or = 1 FDRs about their diagnosis, and most (68%) felt that it was the patient's responsibility to notify at-risk relatives. CONCLUSIONS: Most colorectal adenoma patients younger than 60 years are unaware of the familial implications of their diagnosis and therefore unlikely to notify at-risk FDRs.  相似文献   
480.
A symptom prevalence survey was conducted of a neighborhood exposed to airborne hazardous wastes. Residents' responses were compared to those of a nearby control population. The results revealed that the exposed group had more self-reported complaints referable to the respiratory system (wheezing, shortness of breath, chest discomfort, persistent colds, coughs), constitutional complaints (always fatigued, bowel dysfunction), and irregular heart beat. When the effect of a documented irritant source in a small portion of the control population was removed, the exposed group also complained more often of irritation of the eyes and nose. There was a biological gradient for several of these effects. Efforts to eliminate the influence of confounding and recall bias are discussed. The results suggest either that the general population reacts to chemicals at levels much lower than the available occupational literature would indicate or that the effects are more long lasting than previously thought.  相似文献   
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