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91.
Twenty-eight patients had combined conventional drip infusion CT scans. The information about the anatomic location of the lesion, its configuration, its cross-sectional appearance, its vascularity (as determined by dynamic signature curves), and its clinical presentation were considered as a single overall unit. This diagnostic approach allowed a diagnosis to be made on virtually all of these enhancing lesions without resorting to either a digital venous imaging study or angiographic procedure. In 17 of these cases, such an invasive second procedure was performed either to confirm the CT impression as part of this study or as part of a therapeutic embolization procedure. 相似文献
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Agrawal S Bhupinderjit A Bhutani MS Boardman L Nguyen C Romero Y Srinivasan R Srinvasan R Figueroa-Moseley C;Committee of Minority Affairs Cultural Diversity American College of Gastroenterology 《The American journal of gastroenterology》2005,100(3):515-523
Colorectal cancer in African Americans has an increased incidence and mortality relative to Whites. The mean age of CRC development in African Americans is younger than that of Whites. There is also evidence for a more proximal colonic distribution of cancers and adenomas in African Americans. African Americans are less likely to have undergone diagnostic testing and screening for colorectal cancer. Special efforts are needed to improve colorectal cancer screening participation rates in African Americans. Clinical gastroenterologists should play an active role in educating the public and primary care physicians about special issues surrounding colorectal cancer in African Americans. Community healthcare groups and gastrointestinal specialists should develop culturally sensitive health education programs for African Americans regarding colorectal cancer. The high incidence and younger age at presentation of colorectal cancer in African Americans warrant initiation of colorectal cancer screening at the age 45 yr rather than 50 yr. 相似文献
94.
Couch FJ Johnson MR Rabe K Boardman L McWilliams R de Andrade M Petersen G 《Cancer research》2005,65(2):383-386
Biallelic mutations in Fanconi anemia complementation group genes disrupt DNA repair and result in the complex Fanconi anemia phenotype. In addition, germ line mutations in the BRCA2/FANCD1 Fanconi anemia complementation group gene have also been implicated in predisposition to a number of cancers including pancreatic cancer. The recent identification of FANCC and FANCG mutations in resected pancreatic tumors selected for loss of heterozygosity on chromosome 9, some of which were present in the germ line DNA, suggests that inactivation of these and other Fanconi complementation group genes may contribute to pancreatic cancer. To further assess the relevance of FANCC and FANCG mutations to pancreatic cancer we conducted a mutation screen of these genes in DNA from blood of 421 sequentially collected pancreatic cancer cases diagnosed at the Mayo Clinic. Two truncating FANCC mutations but no truncating FANCG mutations were identified in young onset (<55 years) pancreatic cancer cases with no family history of pancreatic cancer. Both mutations were associated with loss of heterozygosity of the wild-type allele in corresponding pancreatic tumors. In addition, no truncating mutations were identified in germ line DNA from blood of 658 control individuals undergoing routine colonoscopy. Taken together these data support the assertion that inherited mutations in FANCC can predispose to pancreatic cancer. 相似文献
95.
You YN Dozois EJ Boardman LA Aakre J Huebner M Larson DW 《Annals of surgical oncology》2011,18(9):2469-2476
Background
Recent population-based studies have highlighted a disproportionate increase in the incidence of rectal cancer among adults younger than aged 50 years. To determine whether different intervention and surveillance strategies might be needed for younger patients, the patterns of care and oncologic outcomes among adults younger than aged 50 years with rectal cancer were investigated. 相似文献96.
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Objective
To explore the quantitative and qualitative aspects of friendship in people with schizophrenia. To examine emotional and behavioural commitment, experiences of stigma, and the impact of illness factors that may affect the making and keeping of friends. The difference in the perception between the researcher and participants of the presence of problems in friendships was also investigated.Methods
The size and quality of the social networks of 137 people with established schizophrenia or schizoaffective disorder, aged 18–65 in one geographical area of southeast England was ascertained using a semi-structured interview. Qualitative aspects of friendship were measured using objective, pre-determined, investigator-rated criteria.Results
The mean number of friends reported by respondents was 1.57. Men were less likely to report friendships than women (29 vs. 53%, χ 2?=?13.51, df 1, p?0.001). Of the 79 people who had a friend, 75 named someone amongst fellow service users. The quality of these friendships was generally good. Emotional commitment to friendship and mistrust were more important than current clinical state in determining whether or not the participant has friends. Most of those without friends did not see the lack of friendship as a problem. The researcher was up to three times more likely to report a problem than the participant.Conclusions
The friendship network size was found to be small but the quality of friendship mostly positive and highly valued. The majority of friendships were with other service users made during attendances at day hospitals and drop-in centres thus underscoring the importance of this service provision. Psychosocial intervention programmes need to take into account psychological factors that impact upon friendship. 相似文献100.
Christopher F. Shay Ian S. Boardman Nicholas M. James Michael E. Hasselmo 《Hippocampus》2012,22(8):1733-1749
The resonance properties of individual neurons in entorhinal cortex (EC) may contribute to their functional properties in awake, behaving rats. Models propose that entorhinal grid cells could arise from shifts in the intrinsic frequency of neurons caused by changes in membrane potential owing to depolarizing input from neurons coding velocity. To test for potential changes in intrinsic frequency, we measured the resonance properties of neurons at different membrane potentials in neurons in medial and lateral EC. In medial entorhinal neurons, the resonant frequency of individual neurons decreased in a linear manner as the membrane potential was depolarized between ?70 and ?55 mV. At more hyperpolarized membrane potentials, cells asymptotically approached a maximum resonance frequency. Consistent with the previous studies, near resting potential, the cells of the medial EC possessed a decreasing gradient of resonance frequency along the dorsal to ventral axis, and cells of the lateral EC lacked resonant properties, regardless of membrane potential or position along the medial to lateral axis within lateral EC. Application of 10 μM ZD7288, the H‐channel blocker, abolished all resonant properties in MEC cells, and resulted in physiological properties very similar to lateral EC cells. These results on resonant properties show a clear change in frequency response with depolarization that could contribute to the generation of grid cell firing properties in the medial EC. © 2012 Wiley Periodicals, Inc. 相似文献