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Cluster analysis of performance during acquisition of a place-learning task in the water maze distinguished between subpopulations of aged rats (25-27 months) classified as moderately (AMI) or severely impaired (ASI) in comparison with young adults (3-5 months). Using a slice-superfusion device, electrically or nicotine-evoked release of dopamine from striatum was assessed in the presence of GR-55,562 (5-HT(1B) receptor antagonist), methiotepin (mixed 5-HT(1/2) receptor antagonist) and/or sulpiride (D(2)/D(3) receptor antagonist). The main neuropharmacological results demonstrated age-related alterations in the 5-HT(1B)- and D(2)/D(3)-mediated modulation of electrically evoked striatal dopamine release. Regression analyses indicated a possible contribution of such alterations to the age-related behavioural deficits: the larger the deficit, the weaker the electrically evoked release under 5-HT(1B) and D(2)/D(3) receptor blockade. Extending our recent report on the modulation of striatal acetylcholine release in aged rats [Cassel et al., 2007. Neurobiol. Aging 28, 1270-1285], these new findings make dopaminergic and serotonergic functional alterations potential candidates to participate in age-related deficits in the water maze, most probably in interaction with formerly described cholinergic dysfunctions.  相似文献   
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Fifty-seven patients were studied over a period of three years to analyse the efficacy of surgical pleurectomy for spontaneous pneumothorax. Thirty-one and 26 patients underwent open and video-assisted thoracoscopic surgery (VATS) pleurectomy, respectively. VATS was the main modality used for primary spontaneous pneumothorax (PSP) (21 vs. 8). However, secondary spontaneous pneumothorax (SSP) was mainly managed with open pleurectomy (23 vs. 5). The median operating time was significantly longer in open group (72.4 vs. 55 min; P=0.005). The amount of analgesia required in the first five days was significantly more in open group (108 mg vs. 46.9 mg; P=0.02). Chest drainage was significantly more in open group (1027.1 ml vs. 652.8 ml; P=0.04). However, chest drain duration and hospital stay had no significant difference. VATS emerged as a cost-effective modality (1770 pounds vs. 3226 pounds). The ability to return to work was significantly earlier in VATS group in PSP patients (6 weeks vs. 10 weeks; P=0.007). There were 3 (5.27%) recurrences in VATS group for patients with SSP. This experience suggests that VATS pleurectomy is an appropriate modality for PSP. However, open pleurectomy is a viable alternative to treat SSP.  相似文献   
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Cotard's syndrome is a rare syndrome, characterized by the presence of nihilistic delusions. The syndrome is typically related to depression and is mostly found in middle-aged or older people. A few cases have been reported in young people with 90% of these being females. We present a case of a young pregnant woman suffering from Cotard's syndrome. This is the first report of this syndrome in a pregnant woman. The case was diagnosed late, due to lack of awareness of psychiatric problems in primary care physicians resulting in undue suffering, loss of precious time and resources for the patient. Besides highlighting the rare combination of pregnancy and Cotard's syndrome this report delineates the difficulties faced by patients with such symptoms in a low resource setting.  相似文献   
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An overview of cancer statistics and trends for selected cancers and all sites combined are given based on data from the Surveillance, Epidemiology, and End Results Program. Median age at diagnosis for all sites combined shows a 2-year increase from 1974 through 1978 to 1999 through 2003. Changes in cancer incidence rates from 1975 through 2003 are summarized by annual percent change for time periods determined by joinpoint regression analysis. After initial stability (1975-1979), incidence rates in women for all cancer sites combined increased from 1979 through 2003, although the rate of increase has recently slowed. For men, initial increases in all cancer sites combined (1975-1992) are followed by decreasing incidence rates (1992-1995) and stable trends from 1995 through 2003. Female thyroid cancer shows continued increasing incidence rates from 1981 through 2003. Blacks have the highest incidence and mortality rates for men and women for all cancer sites combined. Based on 2001 through 2003 data, the likelihood of developing cancer during one's lifetime is approximately one in two for men and one in three for women. Five-year relative survival for all stages combined (1996-2002) ranges from 16% for lung to 100% for prostate cancer patients. Cancer survival varies by stage of disease and race, with lower survival in blacks compared with whites. The risk of developing subsequent multiple primary cancers varies from 1% for an initial liver primary diagnosis to 16% for initial bladder cancer primaries. The impact on the future U.S. cancer burden is estimated based on the growing and aging U.S. population. The number of new cancer patients is expected to more than double from 1.36 million in 2000 to almost 3.0 million in 2050.  相似文献   
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Pacemaker migration is a rare, but important, complication of pacemaker insertion mainly documented in children. We report the case of a 60-year-old woman who was admitted with right iliac fossa pain thought to be caused by appendicitis. She was noted to have both an epicardial and endocardial pacemaker in situ. Imaging and laparoscopy revealed migration of the epicardial pacemaker to the right iliac fossa. We describe the possible mechanisms of pacemaker migration.  相似文献   
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